To keep your child on your rhealth insurance until age 26, do they have to be living with you" Do they have to be your dependant?

in most cases yes

I believe the child has to be your dependent.I know they can be going to school and still be your dependent

I'm not sure what the exact law is, but I kept my daughters on until they were 26. One didn't live at home and I didn't claim her as a dependent, but she was I believe 24 when the ACA passed, not on my coverage for long. The other came and went from home (going to college, undergrad at school, graduate she lived at home), the whole time I claimed her as a dependent.

My coverage was through my employer, I didn't try and hide their situations. I didn't get any pushback.

I suggest you go for it, be honest if asked questions, but if nobody pushes back......:)