This article originally appeared on InStyle

It's hard to believe Reese Witherspoon's eldest son is now 14 years old.

The Oscar winner kicked off Deacon Phillippe's birthday with a sweet note on Instagram Monday, giving us the feels as she reflected on the person he's become. "Happy Birthday @deaconphillippe! Fourteen years ago you came into my life, and have made me laugh and smile everyday since," she captioned a shot of him. "I love your kind heart and your joyful, adventurous spirit. Hope you have the best day ever!! Love, Mom."

In the photo, Philippe, who looks like a mix of Witherspoon and his dad Ryan Phillippe, flashes a smile in a black shirt in the midst of a fishing session.

His sister, Ava, who turned 18 last month, soon chimed in with an adorable post of her own to celebrate her bro's big 1-4. She shared a throwback snap of herself cradling Deacon in her arms when he was a baby. "#14 years ago today!! Happy birthday, @deaconphillippe!," she wrote alongside the snap on Instagram. "Congrats on being way cooler at 14 than I am at 18. I'm so lucky to have you around. Love you so much, and I hope you have an awesome day!"

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As the tributes rolled in, dad Ryan posted one too. His 'gram showed off Deacon's love for football (and the Philadelphia Eagles, specifically) while he was at it. "Oh yeah, @philadelphiaeagles, get the win for my boy's birthday today!! #FlyEaglesFly," he captioned a shot of his son as a child rocking an Eagles jersey.

Witherspoon is also mom to 5-year-old Tennessee with husband Jim Toth. The tot celebrated his birthday last month as well.

Happy birthday, Deacon!