The former couple got together over the weekend to celebrate the milestone moment for their son.
Reese Witherspoon and her ex, Ryan Phillippe just got together for a very special occasion. The former couple reunited to celebrate their son, Deacon's, 18th birthday over the weekend. Ryan took to Instagram to share some family photos of the trio as they ushered Deacon into adulthood.
"Happy 18th birthday to our gorgeous, smart, talented, and caring son," Ryan wrote. "You are a true light in this world and are so loved by all who know you. We are lucky to be your mom and dad. Love you, pup..(I’d say we did pretty good @reesewitherspoon)."
Deacon replied to his dad's proud post, commenting, "Thanks dad!! I love you," with Reese adding, "So proud of our boy ... I mean our ADULT Son! 😮❤️."
The Morning Show actress shared a tribute of her own to the 18-year-old. The 45-year-old mother-of-three shared a series of photos of Deacon over the years, including some sweep snaps of the now-adult as a little boy.
"How did this happen?!! @deaconphillippe is 18?!! One day he was trading Pokémon cards, singing Bruno Mars songs, and playing American Ninja Warrior in the backyard. The next day, he is taller than me, cooking the family steaks on the grill and making his own music with his best friends," she wrote.
Reese couldn't contain her pride over the "young man" she says Deacon is becoming as she penned the heartfelt tribute Saturday.
"My heart is bursting with pride about the young man he is becoming. Happy 18th Birthday Deacon! I love you to the moon around the sun and all the stars ✨ 🥺❤️🎂," Reese who also shares 22-year-old, Ava, with her ex-husband, added.
In August, Ryan shared a photo alongside his lookalike son during a family vacation in Jemez Springs, New Mexico. The 47-year-old actor's post included many pics from his and Deacon's time at McCauley Warm Springs. The father-son duo posed for two shirtless selfies, clearly showing off their lookalike features.
Additionally, Ryan's post featured pics and videos of the stunning landscape, as well as a solo shot of each of the guys enjoying the clear water.
"The rocky uphill hike was well worth the warm woodland baptism that followed," Ryan captioned his post, with Deacon commenting, "And the viddles."
Back in 2016, Ryan talked to ET about co-parenting with Reese, specifically over the holidays.
"We trade off," he said at the time. "You have to get to that point as a divorced parent, as any parent, where you're not putting yourself first. You want the kids' experience to be its own and not like, 'Well, I need to have my time!' We have been very good about that."
Watch the video below for more on Ryan and Reese's kids.