Michael Clarke Duncan on the red carpet in 2012

What stars have died that you didn’t know about? When stars such as Regis Philbin or Glee‘s Naya Rivera passed away, their deaths were met with massive tributes and worldwide headlines. Sometimes, however, the passing of a celebrity can fly under the radar of fans — who may not even realize the stars they’ve enjoyed watching for years are no longer living.

While the work these celebs have done in film and television lives on, those who admired the deceased are often saddened when they realize that these celebrities have died. It’s doubly depressing when these beloved celebrities aren’t afforded the kind of fanfare that they deserved, with news of their deaths quietly receding into the endlessly churning news cycle. Yet regardless of what led to the deaths of these folks, be it illness, addiction, or an unanticipated accident, the one thing that cannot be denied is that they will be missed.

From beloved cast members of hit television series to lesser-known character actors with familiar faces, read on to learn about stars you might not know have died.

Natasha Richardson died in a tragic skiing accident

Natasha Richardson, smiling on the red carpet

As an actress, Natasha Richardson was known for her roles in such films as The Parent Trap and Nell. Richardson was also famous for her family connections, as the daughter of Oscar-winner Vanessa Redgrave and sister of actress Joely Richardson. She also had a famous spouse, actor Liam Neeson, who has a tragic real-life story.

Richardson was vacationing at Canada’s Mont Tremblant ski resort in 2009 when she fell while taking a skiing lesson. As ABC News reported, she initially claimed to feel fine, even joking about her fall. A member of the ski patrol, however, suggested she see a doctor. Insisting she was fine, Richardson ultimately returned to her hotel room. Shortly thereafter, she was rushed to a nearby hospital via ambulance. Sadly, after being airlifted to a hospital in New York City, she passed away at age 45. The cause of death was determined to be "an epidural hematoma due to a blunt impact to the head."

Neeson later paid tribute to his late wife in a since-deleted Facebook post, reported VIP. "Spend time with your spouses. Treat them well," he wrote. "Because, one day, when you look up from your phone, they won’t be there anymore."

Harry Potter actor Richard Griffiths died during heart surgery

Richard Griffiths wearing a tuxedo

British character actor Richard Griffiths was known for roles on both the big and small screens, such as the lecherous Uncle Monty in the British cult comedy Withnail & I, and the pie-baking police inspector Henry Crabbe in the U.K. series Pie in the Sky. Griffiths’ most impactful role, however, was certainly Vernon Dursley, the ill-tempered uncle of the titular wizard in the Harry Potter film franchise.

In 2013, Griffiths passed away at 65; his agent, Simon Beresford, told the Associated Press that his death was due to "complications following heart surgery."

His Harry Potter co-star Daniel Radcliffe, who also appeared alongside Griffiths in a 2008 Broadway production of Equus, paid tribute. "Richard was by my side during two of the most important moments of my career," said Radcliffe in a statement obtained by CBS News. "Before official production had even begun on Potter, we filmed a shot outside the Dursleys’, which was my first ever shot as Harry. I was nervous and he made me feel at ease." When they reunited for Equus seven years later, it marked Radcliffe’s first time acting onstage, and Griffiths’ presence once again calmed him.

That ’70s Show’s Lisa Robin Kelly died after a sad descent into addiction

Lisa Robin Kelly in front of cars in a city

Viewers of That ’70s Show will certainly recall actress Lisa Robin Kelly, who played Laurie Forman, the sarcastic older sister of Topher Grace’s character, Eric Forman. However, those same viewers were no doubt confused when Kelly’s character was written out of the show in 2001. Although the actress returned for a few episodes subsequently, the role was then recast with a different actress, Christina Moore, for the series’ remaining seasons.

Kelly returned to the spotlight in 2010, albeit not the way she would have preferred, due to a DUI arrest. In a 2012 interview with ABC News, she explained that she parted ways with That ’70s Show after developing a "drinking problem," which she said stemmed from becoming despondent in the wake of suffering a miscarriage.

The following year, Kelly entered a drug rehabilitation center. It was there, reported The New York Times, that she died in her sleep. She was just 43. According to TMZ, Kelly’s death was determined to be accidental, the result of an overdose brought on by "multiple drug intoxication."

Actor-director Harold Ramis died after fighting a rare disease

Harold Ramis wearing glasses and smiling

Harold Ramis is familiar to fans for his onscreen roles alongside Bill Murray, first in the military comedy Stripes, and then as the bookish Egon Spengler in Ghostbusters. However, his biggest successes took place behind the camera. After co-writing the script of mega-successful college comedy Animal House, Ramis branched out as a director, helming a series of comedy blockbusters including National Lampoon’s Vacation, Groundhog Day, and Analyze This.

When Ramis passed away in 2014, his obituary in the Chicago Tribune revealed he’d been suffering for years from autoimmune inflammatory vasculitis, a rare condition that causes inflammation of blood vessels. Complications from the disease were severe, ultimately resulting in his death at age 69.

In her memoir, Ghostbuster’s Daughter: Life with My Dad, Harold Ramis, Lily Ramis Stiel recounted how her father’s failing health led to the end of a decades-long feud that developed between her father and Murray. "In classic Bill fashion, he showed up at the house, unannounced, at seven a.m., with a police escort and a dozen doughnuts," she wrote. While Ramis "wasn’t able to talk much by that point," the pair "spent a couple hours together, laughed a little, and made their peace."

Fresh Prince star James Avery died after open-heart surgery

James Avery

Fans of The Fresh Prince of Bel-Air (which just got unexpected news) loved to watch Will Smith hilariously face off with his character’s wealthy uncle, Philip "Uncle Phil" Banks, played to imperious perfection by James Avery. While the ’90s-era sitcom remains Avery’s most iconic role, he amassed a lengthy roster of screen credits that spanned four decades. That included both TV guest spots in shows ranging from L.A. Law to Grey’s Anatomy, and an impressive body of work as a voice actor in animated projects.

In 2014, CNN reported that Avery had died on Dec. 31, 2013, due to complications from open-heart surgery. Avery’s Fresh Prince co-star Joseph Marcell — a.k.a. Banks family butler Geoffrey — described Avery to CNN as "a marvelous man and a truly wonderful actor… He strove to present an Uncle Phil that everybody wishes was their uncle." Smith likewise paid tribute. "Some of my greatest lessons in acting, living and being a respectable human being came through James Avery," he wrote on Facebook.

In a lecture for the New York Film Academy, Avery explained how he approached his vocation. "You could either be a movie star or an actor. I’m an actor," Avery said. "But I’ve done pretty good."

Actress Marcia Wallace died after fighting pneumonia

Marica Wallace posing on the red carpet

Back in the 1970s, Marcia Wallace got big laughs as the wisecracking, crimson-haired receptionist Carol Kester on beloved TV sitcom The Bob Newhart Show. Among her many subsequent screen credits, Wallace also gained fame for lending her distinctive voice to Edna Krabappel, Bart Simpson’s cynical schoolteacher on The Simpsons.

In 2013, the Los Angeles Times reported that Wallace passed away at age 70. Her son, Michael Hawley, told the Times that her health had been poor during the months leading to her death, which came about due to complications related to pneumonia. Wallace had previously undergone surgery for breast cancer, but Hawley said she’d been declared cancer-free; the death certificate, however, was obtained by TMZ, and reportedly indicated the primary cause of death as "pneumonia, sepsis (inflammation due to infection), and chronic obstructive pulmonary disease (COPD)," with cancer listed as a "significant condition."

In a statement to The Hollywood Reporter, Simpsons executive producer Al Jean said she was "beloved by all at The Simpsons and we intend to retire her irreplaceable character." True to Jean’s word, Edna Krabappel was written out of the show, with the show offering the character a touching tribute.

The Green Mile’s Michael Clarke Duncan died after suffering a heart attack

Michael Clarke Duncan smiling on the red carpet

Michael Clarke Duncan was an imposing figure onscreen, with his muscled physique on display for the breakout role that remained his best-known: inmate John Coffey, whose supernatural abilities are at the center of Stephen King’s The Green Mile. Other film roles included Planet of the Apes, The Scorpion King, and Daredevil, while his TV work included being cast as a series regular in short-lived Fox series The Finder.

Duncan was just 54 years old when he died in September of 2012. According to the actor’s obituary in The New York Times, he died from complications stemming from a heart attack he had suffered less than two months earlier.

At the time of his death, Duncan was engaged to Omarosa Manigault Newman, who opened up about the night of his heart attack in an interview with OWN’s Where Are They Now? She recalled hearing him "laboring, trying to breathe and then I didn’t hear anything and I just jumped up." When she realized Duncan had ceased breathing, she performed CPR and was able to get his heart beating, and rush him to a hospital. "He fought," she said. "After two months of fighting, he passed away."

Poltergeist star Heather O’Rourke’s death sparked rumors that the movie was cursed

Heather O'Rourke in the film Poltergeist

One of the biggest, scariest horror hits of the ’80s was Poltergeist, in which a platinum-haired youngster played by child actor Heather O’Rourke communicated with a supernatural entity via the static on a television screen. O’Rourke reprised the role in two sequels before passing away unexpectedly in 1988 during surgery to repair a previously undetected bowel defect. She was just 12.

According to a report from the Associated Press, the official cause of O’Rourke’s death was "septic shock due to congenital stenosis of the lower intestine." Additionally, "the circumstances of her death were extremely unusual," with a gastroenterologist declaring he found it very strange that she never experienced any prior symptoms. "It’s weird," O’Rourke’s manager, Mike Meyer, shared. "She was completely healthy Saturday, they thought she had the flu on Sunday, and she was dead on Monday."

Years later, a bizarre rumor proliferated, claiming that Poltergeist was cursed. In addition to O’Rourke’s death, reported the New Zealand Herald, actress Dominique Young (who played the older sister of O’Rourke’s character) was strangled to death by her boyfriend shortly after the film’s release. Additionally, actors Julian Beck and Will Sampson both passed away after appearing in Poltergeist II, fueling additional speculation.

Actor Taylor Negron died after fighting cancer

Taylor Negron on the red carpet in Los Angeles

While Taylor Negron‘s name may not be instantly recognizable, his face will no doubt be familiar. Negron boasted an extensive array of credits on both the small and large screens, including TV series ranging from Curb Your Enthusiasm to Party of Five, and films such as Fast Times at Ridgemont High (in a small but memorable role as a pizza delivery guy who delivers a pie to Sean Penn’s Jeff Spicoli during class). In 2015, Deadline reported that Negron passed away at age 57 after a lengthy battle with cancer.

The year before his death, Negron gave an interview to KCET, discussing his film and television work. "I became the alternative everyman in movies," he said, reflecting on being "that guy" in so many projects.

One of his flashier roles was playing the villain opposite Bruce Willis in the 1991 action-comedy The Last Boy Scout. "It wasn’t a stretch, but it came as a surprise to me," he said of being cast in such a plum part. In fact, when he was first offered the role, "I thought it was a joke and they had made a mistake in the printing — that I was going to play the first goombah to the left."

John Spencer’s West Wing character’s heart attack eerily predicted his own death

John Spencer standing in front of law books

Acting professionally since the ’60s, John Spencer had amassed a lengthy list of credits in film and television when he was cast as White House Chief of Staff Leo McGarry in The West Wing. Spencer’s performance won him critical acclaim, along with five Emmy nominations (and one win). Sadly, the most celebrated role of Spencer’s career would also be his last.

In the show’s sixth season, a plot twist featured Leo suffering a near-fatal heart attack; in a bizarre case of life imitating art, the following year Spencer himself suffered a heart attack at age 58. Unlike Leo, Spencer didn’t survive. According to the actor’s obituary in The New York Times, Spencer was taken to a Los Angeles hospital, where he was declared dead.

In a 2014 retrospective about the show for USA Today, actor Dulé Hill (who played presidential aide Charlie Young), admitted that the loss of Spencer took a toll on the show. "West Wing without John Spencer isn’t The West Wing, to me anyway," he said.

Frasier dad John Mahoney died of complications from throat cancer

John Mahoney smiling at a red carpet event

One of the biggest television hits of the ’90s, Frasier ran for 11 successful seasons before saying goodbye in 2004. Throughout it all, John Mahoney played Martin Crane, the cranky father of sibling psychiatrists Frasier (Kelsey Grammer) and Niles (David Hyde-Pierce). On the silver screen, Mahoney delivered standout performances in such films as Say Anything (here’s what only adults notice about the film) and Barton Fink, in addition to a particularly memorable performance in Moonstruck, as a would-be suitor who tries to charm the mother (Olympia Dukakis) of Cher’s character.

Mahoney passed away at age 77 in 2018, with The Guardian reporting that his death was due to complications related to throat cancer.

In an October 2017 interview with Fox News, less than four months before his death the following February, Mahoney was optimistic that he’d beaten cancer a second time; he had first been diagnosed 20 years earlier, just as his Hollywood career was heating up. "I had made some of my biggest movies when I was diagnosed," he said of his previous cancer battle. "I wasn’t going to let this cancer get me. I waited too long to do this."

Dancer-actor Gregory Hines dies after battling cancer at age 57

Gregory Hines outside on a city street

Gregory Hines was a multitalented actor, singer, choreographer and tap dancer who starred in such films as The Cotton Club, Running Scared, and A Rage in Harlem. He also headlined his own eponymous TV sitcom, The Gregory Hines Show, and played a recurring role in NBC sitcom Will & Grace as Will Truman’s (Eric McCormack) ruthless boss, Ben Doucette. When Hines passed away in 2003 at age 57, his obituary in The New York Times revealed the cause of death to be cancer.

A report in the National Enquirer divulged that Hines had been diagnosed with liver cancer two years earlier, but had kept his diagnosis a secret from those he worked with. According to a source, "No one except his family knew how sick he was."

The insider also revealed that the Will & Grace cast was devastated by news of Hines’ death. "When news like this hits you so suddenly, you’re in a state of shock," Sean Hayes told the Enquirer. "I couldn’t believe it. I immediately thought of his family and what they must be going through."

An enlarged heart led to the death of Footloose star Chris Penn

Chris Penn in front of a wooden wall

Brother of Oscar-winner Sean Penn and musician Michael Penn, Chris Penn was known for memorable roles in Rumble Fish, Footloose, Reservoir Dogs, Mulholland Falls, and many more movies. He was just 40 years old when he died, reported The Star-Ledger; his lifeless body was discovered in early 2006 in a California condo. An LAPD lieutenant indicated that there didn’t appear to be any "obvious signs of foul play."

The truth emerged the following month when TV’s Access Hollywood revealed details from the coroner’s investigation, reported People. While the official cause of death was an enlarged heart (Penn’s weight had swelled to more than 300 pounds), a toxicology report detailed the various substances present in his body at the time of his death: Valium, morphine, marijuana, an antihistamine, and codeine.

Actress Lori Singer, who worked with Penn on Footloose, told the New York Post she was "devastated" by the loss. "He had the understated brilliance of a true artist. He was real in person and in his acting. He was the real thing," she said.

National Lampoon’s Vacation star Dana Hill died from a medical condition she didn’t know she had

Dana Hill sitting in front of a row of books

Dana Hill was one of the most ubiquitous child actors of the early ’80s, appearing in TV guest spots on series ranging from Mork & Mindy to Magnum P.I. Perhaps her best known role, however, was Audrey Griswold in the 1985 sequel National Lampoon’s European Vacation. After that, she segued into a career as a voice actor in animated series such as Rugrats and Sonic the Hedgehog.

As People reported, Hill (whose real name was Dana Hill Goetz) was diagnosed with type 1 diabetes when she was 10, a condition that stunted her growth — and allowed her to play characters far younger than she actually was. Sadly, the diabetes also left her kidneys damaged, causing her to be frequently hospitalized over the years. Those health issues came to a head in May 1995 when she went into a diabetic coma, and then suffered a stroke.

Forty days later, she died at age 32. Speaking with People, her mother said that Hill "just gave up… She had succeeded at everything she ever tried to do. There was only one area of her life where she was a loser, and that was her infirmity."