Kailyn Lowry shocked fans by posting a photo of herself and baby daddy Chris Lopez celebrating their baby son Lux's first birthday!

On Sunday, August 5, Lowry marked little Lux's milestone by sharing the shot on Instagram.

It showed the Teen Mom 2 star, 26, and Lopez on their knees on either side of Lux sitting in his high chair. The proud parents smiled at the boy.

Lowry wrote as a tender caption, "Happy FIRST birthday to my baby... who's not a baby any longer. I love you."

But Lopez being there had some followers confused as the two split up long ago and have weathered tons of drama.

For example, a Teen Mom 2 episode showed Lopez filing for emergency visitation rights!

But on Sunday, it was all cooing and smiling as Lowry, Lux, and Lopez looked like a happy family.

Fans were thrilled, with one writing, "Awe glad Chris was there! Happy Birthday, Lux."

Another responded via Instagram, "So good to see a family picture ?? love it."

During a recent episode of TM2, Lowry accused Lopez of being an "Instagram dad" who posts photos of his kid but h