JW parents are encouraged to shun their disfellowshipped children. If they are minors living at home, they do not ask them to be kicked out, and allow normal conversation "not related to spiritual things".
So that is the policy, but some parents extreme or liberal. As an adult, I have family that does speak to me, and others that don't. I'm not disfellowshipped, s some have taken it upon themselves to shun me on their own.
Its important to note, if the child no longer lives at home, then they are required to shun them the way they would anyone else. "The spiritual relationship comes before the physical one", is what we would have said.