Kathryn, 26, posted the snaps on Instagram and captioned them, "Our little graduate! can’t believe she is going to be a kindergartner! ? #adulting."
One of the shots showed Kathryn, Thomas, 56, and their son Saint, 3, posing in front of the school. Kensie held on to a bouquet of flowers.
In another pic, Kensie smiled during the graduation and rocked her cap and gown.
The event was a rare outing for Kathryn and Thomas, who split in 2016 after a tumultuous on-again, off-again relationship.
The reunion comes just weeks after Kathryn claimed that Thomas forced her to keep her first pregnancy a secret.
She became pregnant with Kensie in 2014 when she was 22. "I was removed. He moved me immediately to a different state, kept my pregnancy a secret until the day I gave birth," she told People.
"I felt sad and scared and lonely and confused and quarantined and isolated. I was just trying to understand what was going on with the other person — feeling actually happy looking at my child while the other person was not necessarily present, even mentally. I’d cry a lot, it was all new. I didn’t have anyone," she confessed.
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