Much depends on the state laws and the family situation when it comes to estate planning.
When parents become estranged from their children, they need to know how to handle those children in their estate plans. An example was published recently when a woman wrote to the Napa Valley Register to ask about her brother's daughter in "Is daughter really disinherited?"
The woman's brother had a child 30 years earlier. The brother had cut off all contact with the child's mother, when she was under the age of one. The child was later adopted by her stepfather. In his trust, the brother did not mention the daughter by name. However, he used a general disclaimer that he did not want any unnamed relatives to receive anything.
The letter writer wanted to know if this daughter was really disinherited or if she could make a claim against the brother's estate.
In this case, the answer was an easy one. When the daughter was adopted by someone else, any legal relation between the biological father and the daughter terminated. The daughter cannot claim to be a relative for estate law purposes. In cases where a child has not been adopted by someone else, the answer depends on state law. Some states assume that any child not specifically mentioned and disinherited in an estate plan, were left out as the result of a mistake.
Contact an estate planning attorney, if you have questions about estranged children and laws in your state.
Reference: Napa Valley Register (March 15, 2018) "Is daughter really disinherited?"