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 has a small parenting role.
Lopez became furious and wrote online, "Instagram parent" and added, "F--K Teen Mom 2" and "the nerve of the bird in the driver seat."
However, Lowry, who has had three sons with three different baby daddies, recently admitted that Lopez was her first true love and heartbreak.
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The Teen Mom 2 star shocked fans with a Q&A on her blog in June that revealed her love secrets.
Lowry said that her split from Lopez, the father of her third son, was incredibly painful.
"I believe Lux's dad was my first true love...I know, weird, when I had two kids with two other people," the reality star said in her question and answer post.
The reality TV star noted of Lopez, whom she'd split from before Lux was born last year, "This was my first REAL heartbreak, where I loved someone and was IN love with someone. And I felt so abandoned during such a vulnerable time."
Now fans, seeing her posing with Lopez and Lux, wonder if there could be a chance of reconciliation!
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