If there was never an order for support, you're SOL. If he did owe unpaid support, you could try filing a claim against his estate, but I'm betting you're SOL there, also.
No, child support can only be taken from the birth parents.
The father can file for this change.
Yes, provided the separated parent is the father.
Marriage of the mother, father or child have no relationship to the collection of a debt.
Yes, if the father has more time with the child than the mother, she will owe him child support.
no
No, you can't. First, you can't sue a parent for child support. Second, there is nobody to collect it from since your father has passed. However, if your father has an estate you could contact the attorney handling the estate or a private attorney to determine if you have any rights in his estate as an heir at law.
if the mother terminates her rights can he collect child support from the mother if child lives with him?
no the mother should have the legal obligation to take care of the child
no
File for in and they will contact Canada.
Yes, but paternity must be established first.