Jon Gosselin Shares Update on Son Collin After Enlisting in U.S. Marine Corps (Exclusive)

Jon Gosselin is opening up about his son, Collin Gosselin, and how he's doing now that he's enlisted in the Marine Corps.

Jon sat down with ET's Rachel Smith and was joined by longtime girlfriend Stephanie Lebo. The pair opened up about their relationship with Collin, and how he's benefitted from joining the military.

"Collin's super independent, so he lived on his own a little bit during high school like he just wanted to experience that. [Then] he enlisted at 18 and he left when he was 19, [and] I think it taught him to grow up a lot faster," Jon shared.

"I got some letters from him from boot camp, from Parris Island," Jon added. "He's doing super well he just talks about like training... He said he doesn't really have time to do anything [else]."

"It's very structured," Stephanie added.

"It's very, like, at 4 a.m. they get up, they do PT, they go eat, then they go study, classroom, then they eat, then PT, you know?" Jon explained. "It's what he's always wanted to do."

"We sent him gift cards to go shopping but he won't be able to do that until the ninth week," the proud dad added. "[But] he just writes like, 'Hey, I miss you guys, I can't wait to eat a real meal.'"

Collin's enlistment in the Marines comes amid new drama between his father and his mom -- Jon's ex-wife, Kate Gosselin.

Jon and Kate share eight children. Collin is part of a set of 19-year-old sextuplets -- Aaden, Alexis, Hannah, Joel, and Leah -- while 22-year-old Mady has a twin sister, Cara.

Collin has been estranged from his mom after he was institutionalized for behavioral issues as a child. After Jon got Collin out of the facility, the teen, along with his sister, Hannah, went to live with Jon. According to Jon, neither Collin nor Hannah have had a relationship with their fellow sextuplets or older sisters in some time.

Meanwhile, Stephanie had nothing but praise for Collin, calling him a "gentleman," and celebrating his kindness since she's known him over the past few years.

"I mean, he brings flowers and he loves that his dad is happy, so it allows them to be happier," Stephanie said "Things are great."

"I think we built a good solid foundation for Collin to go into the Marines and now he knows he has a strong support system at home," Jon said. "He has good friends that back him up so that he can fulfill his dream of being a Marine and still come home."

"He has great traits that reflect his dad," Stephanie added. "One thing that they have in common, and I love it, is that if one of them says they're going to do something, they always follow through. He has a lot of his father's traits."

For more on Jon and Collin's relationship, see the video below.

Collin Gosselin Thanks Dad Jon Gosselin and His Ex in Moving Graduation Tribute

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