The former couple – who were married from 1999 until 2007 – share two children together, Ava and Deacon.
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And they recently reunited in celebration of their son following his graduation.
Ryan, 47, shared a series of fun family snapshots showing the trio enjoying a "homeschool graduation" together. The actor took on the role of 'principle' and can be fully dressed up in a cap and gown as he shakes his son's hand in a short video.
Reese, meanwhile, also appears in the clip, fishing her son's cap out of the swimming pool after his 'ceremony'.
Ryan shared a series of photos from the 'homeschool graduation'
"Homeschool graduation feat. @matt_sinn & @benmassing," Ryan captioned the post. "Reese w the cap grab [crying laughing emoji]. (i played principal)."
Deacon was among the first to respond, sweetly writing "Best dad ever," in the comments. A huge number of fans remarked how nice it was to see the group all together, with one writing: "Best co-parents!"
Reese and Ryan have remained on really good terms
Just last year, Reese and Ryan again reunited in celebration of their son's 18th birthday.
Proud dad Ryan took to Instagram to share a lovely picture of himself, Deacon and ex-wife Reese smiling at the table in a restaurant in front of a birthday cake, alongside a heartfelt message.
The actor wrote: "Happy 18th birthday to our gorgeous, smart, talented, and caring son. You are a true light in this world and are so loved by all who know you."
The former couple reunited last year to celebrate Deacon's birthday
He added: "We are lucky to be your mom and dad. Love you, pup.. (I’d say we did pretty good @reesewitherspoon.)"
Reese was quick to reply to the comment, writing: "So proud of our boy. I mean our ADULT son!" alongside a love heart emoji. Deacon replied too, adding: "Thanks dad!! I love you."
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