The fall is a very special time of the year for Reese Witherspoon.
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Having celebrated daughter Ava's 23rd birthday just last month, the star took to Instagram to mark son Deacon's special day on Sunday.
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Reese shared two snapshots of Deacon in honor of his 19th; one taken recently, and the other a throwback photo from his childhood.
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She proudly wrote: "Big Birthday Love for @deaconphillippe today! The guy who possesses the most joyful energy, endless drive, ambition and talent. And the biggest heart in the world. Could not be more PROUD of you... I love you, D!"
Reese's fans and famous friends were quick to send birthday wishes to Deacon. "Happy birthday!" wrote Julianne Moore, while Gwyneth Paltrow added: "What a babe," along with a red love heart. "HBD Deacon!" shared Kate Hudson.
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Reese shares her two eldest children with ex-husband Ryan Phillippe. The former couple met in 1997 at a party for her 21st birthday and one year later co-starred in the hit film, Cruel Intentions.
They were married from 1999 until 2007 and remain on good terms.
Reese, meanwhile, has been married to talent agent Jim Toth since March 2011 and together they share one son – ten-year-old Tennessee.
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While Ryan hasn't gone on to tie the knot again, he has another daughter, Kai Knapp, 11, from his former romance with Pitch Perfect actress, Alexis Knapp.
In a previous interview with Elle, Reese opened up about her divorce, describing the process as "very humiliating and isolating".
"You see a lot of people play this blame game. Blame, blame, blame. You know? And it's a really easy thing to do, and I'm certainly guilty of it," she admitted.
"[You have to] look at yourself and go, `What part of this do I need to own? Which part of this is my responsibility?' And that's the painful work that you have to go through to hopefully get some real-life knowledge out of it."
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