Old Headshot Day: Stars post hilarious throwbacks on Instagram

We love any excuse for a throwback photo!

Over the weekend, stars belatedly participated in Old Headshot Day, which was on April 26, and the resulting posts were absolutely hilarious.

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Everyone from Reese Witherspoon to Ben Stiller to Natalie Portman and Tori Spelling took part in the fun social media trend, which was exactly what it sounds like: People used the day as an opportunity to share old headshots that ranged from ridiculously adorable to adorably ridiculous, and we've rounded up a bunch of our favorites right here.

See the best celebrity posts from Old Headshot Day:

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