It's back to school season for the Gosselins.
On Monday, Jon Gosselin posted a photo of his son Collin and daughter Hannah on their first day of high school. He also shared photos of himself posing with each of them individually.
"FRESHMAN!!! 9th Grade Wow!!! I can't believe it!!!" he wrote. "Good luck to Hannah and Collin this year!!! Today is their first day of high school!!!!"
"I hope all my kids have a wonderful year in high school this year and have great experiences!!!" he added. "Love all of you!!!"
Jon, 42, shares 15-year-old sextuplets Hannah, Collin, Alexis, Aaden, Joel and Leah with ex-wife Kate Gosselin. The two are also parents to 18-year-old twins Cara and Mady.
Kate, 44, divorced Jon in 2009 after 10 years of marriage.
After a lengthy custody battle, she received primary custody of the children, although Collin and Hannah currently live with Jon full-time. Collin previously spent a little over two years living away from his family in a program for children with special needs.
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Speaking to reporters in December, Jon said while his relationship with Collin and Hannah is strong, he's not in communication with his other children.
"It's what the kids want to do," he said. "If they don't want to talk to me, that's fine, as long as they keep up with their sibling connections."