If a man dies leaving behind a wife and children, don’t assume that there won’t be a guardianship because one parent is still living. While a mother typically has physical custody of the children if the father dies, for much of US history someone would have been appointed guardian to oversee their interest in their father’s estate. That guardian may not have been the mother. This “financial” guardian would not typically have gotten custody of the child–that would remain with the mother.
These guardianship records can provide more details about the father and the children, depending upon the time period. In the United States guardianship records are typically local court records.