Although Collin Gosselin plans to appeal the Marines ... He also shared that writing a letter to his dad, Jon, was the "one thing" that helped him "mentally figure out that there was a way ...

Collin Gosselin gave his dad, Jon Gosselin, a special shoutout on Instagram, following his high school graduation.

Gosselin Sextuplets Turn 19 as Their Dad Jon Shares Throwback Pics: 'I Love You All So Much' Collin Gosselin Gives Rare Interview About Reality TV's Toll on His Family: 'I Think It Tore Us Apart ...