That is dependent on individual state laws.
see link below
The parents of the deceased father (the childs grandparents) can do a paternity test.
No
Yes
a father has a lot of effect
The childs' father, married or not. Your relationship to the father is irrelevent. The father is the first on a long list of family members. Create a living will if that is not acceptable.
No, but the child is potentially eligible for RSDI payments based on his disabled father's eligibility, and these payments would count toward the father's child support obligation.
You can, but eventually the court will question what you are doing.
It isn't the birth father, no one will ever change the childs birth father, but he will legally be the step father,until the divorce comes through.
A childs mother must file a petition for child support in the local family court.
It is possible to legally establish paternity even if the father's name is not on the birth certificate.
If the father was paying you directly, the payments will, of course, cease. If this is the case you must contact the state for assistance. If you were receiving the support payment from the state, then nothing will change and his payments to reimburse the state will become an obligation/lien against him for which he will eventually have to pay the state back.
A child's first connection would be their parents (mother and father). Their next connection would be their siblings (brothers or sisters) if any.