Oops, you blinked and Jon Gosselin and Kate Gosselin's sextuplets are now high school graduates.

As for what the former couple's 19-year-olds are up to next? Well, Collin Gosselin, who alongside sister Hannah Gosselin lives with their dad, shared a heartwarming Instagram post about his plans for this next chapter in his life: He's enlisting in the military.

"Next stop Parris Island," he wrote, referring to the site of the Marine Corps Recruit Depot, "and soon after I will be studying Mechanical and Industrial Engineering in college! Can't wait!!!"

In his June 22 message, Collin also expressed gratitude toward the people who helped him on his journey—including Hannah, who he posted a snap with in their graduation robes.

"I want to first thank my amazing sister, Hannah, for standing by me and supporting me, she is my number 1," Collin wrote. "I would like to thank my dad, who has taught me so much about running into hard times and moving past them, about resilience. Thank you dad for always supporting my decisions, and having my back when I bite off more than I can chew."

Collin further noted the impact Jon's ex-girlfriend Colleen Conrad has had on his life. "I'd like to thank Colleen for rooting for me day in and day out," he wrote. "When you think of someone you want by your side, you think of Colleen. And as I've told her many times, she is my motivator for being successful in this world."

And while his next chapter is taking him to the Marines, Collin also expressed his thanks to the Army officials who helped him find his next move.

"And last but not least I would like to thank my Army Junior ROTC instructors, First Sergeant Dolan, Sergeant Gonzalez, and Major New," he added. "Three of the realest, most humble, and genuine leaders I have ever met. Collectively they have taught me some of the most valuable lessons that I will carry by my side for life. No hate towards the Army, but the challenge of the Marine Corps just appealed to me more. Just thought I'd clarify that."

Collin, Hannah, their sextuplet siblings Leah Gosselin, Alexis Gosselin, Aaden Gosselin and Joel Gosselin, and their older twin sisters Mady Gosselin and Cara Gosselin, 22, rose to fame as children on their parents' TLC reality show Jon & Kate Plus 8, which aired between 2007 and 2009. Following the couple's divorce the latter year, the series became Kate Plus 8 until it ended in 2017.

While Kate obtained custody of all the former couple's kids after their split, Hannah later moved in with her dad, who later obtained full custody of Collin.

And while Collin remains estranged from their mom, Jon confirmed that Kate also attended his and Hannah's graduation on their daughter's invitation. "We saw each other, but there was a whole football field between us," he told People earlier this month. "I talked to Hannah and Collin before graduation to make sure that it was gonna be cordial."

Jon told People in an interview published June 9 that Kate also attended Collin and Hannah's graduation after their daughter invited her. "We saw each other, but there was a whole football field between us," he said. "I talked to Hannah and Collin before graduation to make sure that it was gonna be cordial."

Meanwhile, while Jon remains estranged from the other four sextuplets and the twins, who graduated college this year.

"I had eight graduations this year," he explained. "I only attended one. The only kids I see and talk to are Hannah and Collin. So I've been pretty much estranged from Mady and Cara for nine years."

But he's not closing the door on a possible reconciliation with his other children. "Maybe we'll develop a relationship in the future, but yeah. I can't put all my eggs in one basket like I used to and then be upset about it."

See the Gosselin kids' journeys over the years below:

Collin and Hannah graduate!

On to the next chapter!

It's the show that started it all! Who remembers this cast photo for Jon and Kate Plus 8?

Back in October 2007, Jon and Kate Gosselin gathered their eight kids together for a trip to New York City. First stop? A visit to NBC's Today show. 

"A precious Christmas memory. My 6 were 6. Christmas Eve 2010 and they're SO excited for Christmas!" Kate Gosselin wrote on Instagram with a throwback photo. "Look at those adorable smiles! #TheyAreMyHeart #My8ReasonsToKeepOnKeepingOn #NoMatterWhat #TrueLoveX8." 

 

"I can't believe they're 13!" Kate Gosselin wrote on Instagram when celebrating a major birthday for her sextuplets. 

Jon and Kate Plus 8 viewers loved when the family enjoyed trips together including a 2009 trip to the beach.

Rewind to 2014 when Kate and her children found themselves visiting Alaska. 

Kate also treated her twin daughters Cara Gosselin and Mady Gosselin to a trip to New York City in 2014, where they stopped by the Manhattan Hotel. 

"This was yesterday! Feels like school never ended...and they're already back! #SeniorYear #EighthGrade #ProudMom," Kate wrote on Instagram in 2018.

 

"My beautiful 'little girls' .... they keep reminding me how many days until they turn 14. Today it was '12 days til we turn 14, Mom.' HOW'S THAT EVEN POSSIBLE?!" Kate shared with her followers in 2018. "I told Leah that she's too small to turn 14. She said 'Yeah, true. Are you sure I'm not turning 11 or 12?' I'm positive. I gave birth to you. They'll always be my babies....I love them so very much!" 

"Our big celebration of #15 is finally winding down here! We celebrated ALL DAY LONG, beginning with a present at 6:30 am before school! I'm so very thankful for my ‘babies'.... somehow they are 15 already?!" Kate wrote on the special milestone in 2019. "I'm amazed by them each day! I'm so proud of the positive qualities I've seen developing as they edge closer to adulthood." 

"Happy 15th Birthday Hannah, Collin, Alexis, Aaden, Joel and Leah!!!! Wow I can't believe you are 15!!! Time is flying by!!!" Jon Gosselin shared on Instagram when posing with Hannah and Collin Gosselin. "I love you all very much. I wish you the best day ever and I hope you enjoy your birthday celebrations today and this weekend!!! Love always, Dad." 

"Happy 18th birthday!" Jon wrote on Instagram in 2022. "Today is your birthday we gonna say it loud. I love you. Love, Dad."

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