Kourtney Kardashian reached out to former partner and "baby daddy" Scott Disick online on his birthday.
The picture sees Kardashian straddle Disick in a bikini as she smiles for the camera.
"Happy birthday baby daddy!" she captioned the snapshot.
Kardashian and Disick, who share 6-year-old son Mason, 3-year-old daughter Penelope and 17-month-old son Reign, split in July after nine years of dating.
Disick also received birthday wishes from Kardashian's mom, Kris Jenner, and brother, Rob Kardashian.Sources told People he later celebrated with Kardashian and several members of her family at Nobu restaurant in Malibu.
"Happy Birthday Scott!!" Jenner wrote on Instagram. "Thank you for being a loving and devoted father to my beautiful grandkids. I am so blessed to be able to call you my son. I love you and hope you have the most amazing day!"
Kardashian and Disick have been friendly in recent months, often spending time together alone or with their children.
The reality star was open to a possible reconciliation while discussing her relationship with Disick on the Today show in April.
"We're not getting back together right now, but I don't know what the future holds in life, in God's plan," she said. "But we're just doing our best to be the best parents ... We're friends at this point."
Kardashian and her family star on E! series "Keeping Up with the Kardashians," which airs Sundays at 9 p.m. ET.
Sister Khloe Kardashian is moving on from her own past romance, filing for divorce from estranged husband Lamar Odom again this week.