If your male ancestor died with even a small amount of real estate (lot in town or more) or enough personal property, there might be a guardianship case for his children. The mother likely was the guardian of the child's person, but someone else might have been appointed guardian of the child's estate. Pay close attention to the name of this person. It might have been a male relative or in some cases a step-father and that relationship may never be spelled out in the documents.