Reese Witherspoon/Instagram; Getty Images
Deacon Phillippe rang in his birthday with lots of love from his family.
Several of Deacon's family members wished him a happy birthday with sweet social media tributes. Witherspoon shared several memories of her "wonderful son" on Instagram, including photos of just some of the things she loves about her eldest son.
"Can't believe he is 17!" she wrote on her Instagram Stories alongside a recent picture of Deacon.
Calling him her "adventure-loving travel buddy," Witherspoon also included a picture of the mother-son duo from a previous trip together.
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The Legally Blonde star also featured pictures of her son "making music" and sitting on a boat.
The mom of three also wrote a heartfelt message to her "bright light/ hardworking / fun-loving / music making / deeply kind son" on her main Instagram page.
"What a pleasure to watch you grow into an amazing young man who is always curious and endlessly creative," the mom of three wrote. "Can’t wait to celebrate! I love you so much 🥰🎈."
Deacon's dad Ryan also paid tribute to his son on his Instagram Stories. "Happy birthday to my extraordinary son🌞 ," the actor wrote alongside a picture of Deacon standing by a sunset.
"You're the coolest," he added in another picture. "Happy 17th, my man!!"
The father of two later shared throwback shots of Deacon when he was younger, including a picture of Ryan cutting his hair and walking down a hallway with his son "when he was shorter [than Ryan]."
At the end of the evening, Ryan posted a video from Deacon's backyard birthday celebration. In the clip, Witherspoon is seen bringing out a three-layer cake with a sparkler as Deacon's family sings happy birthday.
Ava made sure to honor her brother on his special day as well.
"Happy Birthday to my bright, fun, cool, and creative lil brother!" the 21-year-old captioned a picture of the siblings together. "I’m so lucky to grow up with you and am so proud of all that you’ve accomplished already."
"You teach me how to see the good in just about everyone and everything and how to live authentically without fear of judgement," she continued. "Thank you for being you! Love, Aves ❤️ #17."