With the advent of DNA testing kits that are prevalent today, many people, who do not know who their parents are, search for them through DNA databases. They will sometime find information on an unknown parent, grand parent, etc.. What does that mean as far as inheritance?
If a person leaves a will, the will determines who inherits his property. Texas does not have forced heirship - a person has to leave some of his property to his children. In Texas, like most states, you do not have to leave anything to your children. What that means is, if the person leaves a will that disposes of all of his property, no one will inherit except those named in the will. That doesn't change based on the fact that he may have had children that he didn't know. If the will leaves property to his "children" or his "descendants" or his "heirs" or something similar without naming who they are, the children who are searching for their parent may be entitled to a share of the property. A person must first determine if there is a will and what the will says. When a will is filed for probate, it is filed with the county clerk in the county where the decedent resided. Once filed, it is a public record and anyone can get a copy.
What if the person dies intestate meaning he dies without a will? In that case, his heirs which include his children will inherit his estate, generally. Depending on when the person died, the wife may inherit all of his community property but the separate property would go to his heirs (his children) with some exceptions.
One big problem with these cases is paternity. If the child seeking their parent was not acknowledged by the parent and the issue of paternity is to be decided by a court, there may be time limits involved. The further back in time it has been since the parent died, the more difficult the process may be.
The issues surrounding these cases need to be discussed with an attorney.