Reese Witherspoon Celebrates Daughter Ava Phillippe's 21st Birthday With New Lookalike Photo

Reese Witherspoon cannot post a picture of herself alongside daughter Ava Phillippe without the whole of social media erupting into a chorus of "OMG! Twins!" It is the law. And now that Ava is 21 — and Witherspoon basically still looks 21 — the resemblance (and everyone's enthusiasm for it) seems stronger than ever. That was made perfectly clear by a new photo the actor posted to Instagram to celebrate her not-so-little girl's birthday.

"Wow! How is it possible that this little girl is now 21 years old? Happy Birthday to my sweet girl who has become the most incredible young woman," Witherspoon wrote in a tear-jerking caption. "Her kindness, her compassion, and her huge heart never cease to amaze me. Ava, there aren’t enough words to describe how proud I am of everything you’ve already accomplished. I cannot wait to see ALL the Good you will put into this world. I love you so much @avaphillippe." But while Reese may not be able to find the words to describe Phillippe, the commenters found one in particular: twin.

After doing a double-take at the gorgeous mother-daughter photo — the angles of their heads emphasizing their similar jawline, their equally wide smiles beaming in unison, their respective blonde hair nearly a perfect shade match — friends and fans couldn't hold back their delight over the duo's resemblance.

“Twins 💝 happy birthday Ava!!!!” Meghan Trainor wrote, and musical director Adam Blackstone agreed with an all-caps, "TWINNING🎉🎉🎉." One fan even wrote, "literal twins," which is impossible since they're mother and daughter, but still.

And they're not wrong! Witherspoon and Phillippe are unmistakably genetically linked. But I'd like to take this opportunity to remind everyone that Phillippe, in fact (OK, in my opinion), actually bears an even stronger likeness to her equally facially blessed father, Ryan Phillippe. Just sayin'.

Either way, one thing is true: Witherspoon's love for her daughter even stronger than her resemblance to her.

More on celebrity moms and their daughters:

• Chrissy Teigen and Daughter Luna Wore the Cutest Disney Princess Sheet Masks Together

• Baby Phat Beauty Just Launched, and It's a Shimmery Retro Dream

• Here's Another Photo Where Gwyneth Paltrow and Apple Martin Look Like Twins

Now check out Loren Gray's 10-minute makeup routine:

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Originally Appeared on Allure