Jon Gosselin wished his twin daughters, Mady and Cara, a happy 15th birthday on Thursday, Oct. 8 Credit: Courtesy of Jon Gosselin/Facebook

That went fast! Jon and Kate Gosselin's twin daughters, Mady and Cara, are already 15 years old. The former reality star-turned-DJ wrote a sweet message to mark the occasion on Thursday, Oct. 8.

"Happy 15th birthday to my daughters Mady & Cara today!!!!" Jon, 38, wrote on his Facebook page. "I can't believe you are 15 years old! I love you and I hope you have an awesome day!"

Jon and Kate, 40, divorced in 2009 after 10 years of marriage, and are famously also parents to 11-year-old sextuplets Aaden, Collin, Hannah, Alexis, Leah, and Joel. Last year, Kate revealed that she has no relationship with her ex.

"I wish that things were better for the kids. It's very clear by now that I'm just trying to preserve what relationship he has with them. I do think it's best for them, but, you know, divorce is hard, period," the Celebrity Apprentice alum told reporters at the Television Critics Association panel on Jan. 16. "But it's really difficult when one parent is in the sabotaging mode. That's been difficult."

Jon, meanwhile, opened up about their kids and estrangement from Kate last month. "My custody is really strange," he exclusively told Us Weekly. "My custody with them is just, like, go out to dinner or whatever and then go home. Their schoolwork — they’re really engrossed in school right now."

They're also into sports, too. Jon told Us that Mady enjoys drama club and Cara loves lacrosse. They both, however, love to shop! "Boys it’s so easy. Boys it’s like, 'You want to go play football?' Okay, awesome. 'Do you want to go fishing? Do you want to go hunting?'" He joked: "But with girls it’s like — I want to go to the King of Prussia [mall]."

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