Weeks before Radar exclusively revealed Jon, 41, won temporary primary custody of the 14-year-old in court on December 4, the father of eight claimed his ex-wife had not "cooperated" with his treatment.
Jon also alleged Kate, 43, was a "trigger" for the boy, who had been placed in a medical facility from 2016 until his long-anticipated release just before Christmas 2018.
"It would not be in the best interests of the minor child…to have independent time with mother or to have mother share legal custody of the minor child because mother has not cooperated with the child's treatment and is a 'trigger' for the minor child," Jon's legal team claimed in Pennsylvania court records on October 24.
In the filing, he requested temporary sole legal and physical custody of Collin.
Less than two months later, Jon won temporary custody of the boy after Kate was a no-show in court.
While Kate has remained mum about the legal battle, Jon claimed on Instagram earlier this month that his ex had "zero" interest in spending time with their son.
Kate has claimed her son has "special needs," which Jon has denied. A family source told Radar in 2016 that Collin, who was once kicked out of school for bad behavior, suffers from "anger issues."
The boy now lives with Jon and his sister Hannah, 14, in their native Pennsylvania.
We pay for juicy info! Do you have a story for RadarOnline.com? Email us at email@example.com, or call us at (866) ON-RADAR (667-2327) any time, day or night.