Reese Witherspoon Celebrates 'Wonderful' Daughter Ava's 23rd Birthday: 'The Most Amazing Woman'

Reese Witherspoon is celebrating her "favorite" daughter on her special day.

On Friday, the Legally Blonde star, 46, paid tribute to daughter Ava with a sweet Instagram post in honor of her 23rd birthday. Witherspoon, who shares Ava with ex-husband Ryan Phillippe, posted a beautiful photo of the look-alike mother-daughter pair posing in front of a beach sunset.

"Happy Birthday to my favorite daughter, Ava !! 🥰Every day that I get to watch you become the most amazing woman is such a gift," Witherspoon wrote. "Your gigantic heart, generous spirit, and endless creativity inspire me every day. I love you so much 💞💫🎂."

The actress also shared an adorable throwback photo of Ava on her Instagram Story as well as a recent shot from when Witherspoon and her daughter went out for dinner and drinks together.

"Can't believe this little girl....is turning 23 today! Happy birthday to the most wonderful daughter! I love you, Ava!" wrote the Big Little Lies star.

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Several of Witherspoon's famous friends sent celebratory messages to Ava in the comments of the actress's post.

"Happy birthday Ava!!! ❤️," wrote Julianne Moore, while Zooey Deschanel dropped a string of heart-eyed emojis.

"Mom daughter twins 😍❤️," added Queer Eye's Jonathan Van Ness.

Witherspoon also shares son Deacon, 18, with Phillippe, as well as son Tennessee James, 9, with her current husband Jim Toth.

Witherspoon was just 23 years old when she had Ava. The actress later spoke about being a young mom during an appearance on The Drew Barrymore Show.

"To be completely candid, I was terrified," Witherspoon told host Drew Barrymore. "I got pregnant when I was 22 years old, and I didn't know how to balance work and motherhood, you just do it … I was just like every other mom and dad trying to figure it out."

Now 23 herself, Ava looks just like her mother — so much so that both Witherspoon and Ava have joked about it in interviews.

"I'm so proud of her. She really rolls with it. I'm sure it's not easy looking exactly like your mother," Witherspoon said in an interview with InStyle.