Jenelle and Nathan got engaged in January, and have one child together, 1-year-old Kaiser. Jenelle says she called off their engagement after Nathan allegedly started an argument with her over him not being able to go out, and for her to find a babysitter for their child.
Jenelle also has a son, Jace, from a previous relationship with her ex, Andrew Lewis -- which Teen Mom 2 viewers will remember from past episodes -- and Nathan also has a daughter, Emery, from a previous relationship.
Jenelle recently celebrated Jace's sixth birthday with a zombie-themed party on Sunday, though Nathan was noticeably absent from the Instagram pics of the celebration.
"My baby turns 6 today! #happybirthdayjace," she wrote.
Nathan was present, however, at Jenelle's graduation last month from Miller-Motte Technical College, when she thanked him for being part of her "biggest support system."
"Thanks to my family for being here as my biggest support system and able to push me through it !!!" she gushed on Instagram about the family pic.
Of course, Jenelle and Nathan have broken up and gotten back together in the past. In late May, she was arrested for domestic violence charges following an argument with Nathan, when the two were broken up. By June, they were back together.
ETonline caught up with original Teen Mom cast members Amber Portwood, Farrah Abraham, and Catelynn Lowell in April, when they dished about learning about parenting by watching their own show. Watch below: