That depends on the State the will is probated in. For instance, in New Jersey, an adult child has no rights to a parents estate if he was not mentioned in the will. The parent has the right to give his possessions to a charity if he wishes to do so.
The rights you have in your estranged husband's estate may vary depending on the laws of the jurisdiction and any legal agreements in place. In general, as an estranged spouse, you may still have a legal claim to a portion of your husband's estate, such as through inheritance laws or a divorce settlement, unless those rights have been legally waived or terminated. It's advisable to consult with a legal professional to understand your specific rights in this situation.
No. Adoption removes the rights to the biological parents' estate.
Children have nearly 0 rights
Children had no 'rights'. The parents had complete control over their families.
Generally, a step-child has no inheritance rights unless they were legally adopted by the decedent. You should consult with the attorney who is handling the estate or with an attorney who specializes in probate in your particular jurisdiction if you think you may have any claim.
to the parents they are blood related to, or adopted, otherwise they must make them an heir by including them in their will.
I am assuming that your grandmother does not have a spouse who is still living. In California, if a resident dies without a will or trust, then the laws of intestate succession are used to determine who will inherit the estate. If your grandmother was not married, then the estate would be divided in equal shares (if they are in the same generation) to her children. If there are no children or grandchildren living, then the estate would go to her parents. If her parents are no longer living, then the estate is distributed to the "issue of the parents." (Issue is the legal term for children, grandchildren, etc.) I am not an attorney but typically, in your situation, you would inherit one third of the estate. (Your father's portion.)
An estranged husband is married and he has all the rights of a surviving spouse if his wife dies. He will inherit an intestate estate according to the laws in the jurisdiction. He will become the sole owner of any property owned by survivorship with his wife if she dies.
No, you have no rights to change your father's will.
If the child was adopted the grand parents have no rights. It would be up to the adoptive parents whether any relationship could be maintained.
Marriage does not affect the rights to inherit in the US.
It is very good. It specifies that the parents are responsible for the safety and welfare of their children.