Reese Witherspoon Celebrates Son Tennessee's 10th Birthday: 'So Lucky to Be Your Mama'

Reese Witherspoon/Instagram

Tenn turns 10!

On Monday, Reese Witherspoon honored her son Tennessee James, whom she shares with husband Jim Toth, as he celebrated his 10th birthday. The Legally Blonde star, 46, paid tribute to her little boy with a sweet post on Instagram.

Witherspoon shared a cute photo of a smiling Tennessee wearing a pair of oversized black sunglasses and a blue polo with a starry background.

"Happy 10th Birthday to my wonderful boy, Tennessee!! Your brilliant curiosity and endless energy make me smile every day! I'm so lucky to be your mama. I love you buddy! 💙⚽️⛳️🏈🌟 Tenn turns 10!" the actress wrote.

She also included a heartwarming picture of the pair on a beach together as she hugged her son from behind and rested her chin on his head. "Happy birthday to my sweet boy!" she added.

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Reese Witherspoon/Instagram

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Earlier this month, The Morning Show star paid tribute to her daughter Ava with an Instagram post in honor of her 23rd birthday.

Witherspoon, who shares Ava as well as son Deacon, 18, 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.