Witherspoon’s caption jokingly alludes to a quote from the 2000 comedy Little Nicky, where Witherspoon plays Adam Sandler’s mom (who’s an angel). In the movie, Sandler says, "If you’re my mom, then how come you’re not older?" To which Witherspoon replies: "Angels don’t get any older, son."

While Witherspoon (who was twenty-three at the time) wasn’t old enough to be Sandler’s mother, she had just given birth to Ava Elizabeth Phillippe. And we gotta say, her heavenly costume matched perfectly with that motherly glow.

Many celebrities were enamored with the rare glimpse of baby Ava—like Octavia Spencer, who wrote, "Her little cheeks though." Or Mariah Carey, who said, "So sweet."

Meanwhile, others (like Julianne Moore) commented on the absurdity of the caption, writing, "Wait, what? His MOM ???"

While Witherspoon keeps herself busy with a clothing line, book club and numerous acting gigs, she has always been an extremely dedicated mother. Only last summer, she created a backyard summer camp for her kids to enjoy while they were quarantined.

Bravo Witherspoon. But also, bring on more baby pics!

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