Jennifer Garner's boyfriend, John Miller, appears to show 'insecurity,' a body language expert says. Here's why.

The CaliBurger CEO “has always been supportive of Ben and Jen’s co-parenting relationship but feels Ben crossed the line,” the insider says.

Jennifer Garner and boyfriend John Miller's relationship is "solid," a source exclusively tells Us Weekly. "He doesn't get jealous and understands Jennifer prioritizing her kids," the insider tells Us of Garner's focus on her three children with ex-husband Ben Affleck.