Throughout much of US history, a minor child whose deceased parent had a significant estate would have a guardian appointed for them. This guardian usually was to oversee the financial interests of the child and did not take physical custody (that was usually left to the mother if she survived). Typically this guardian was a male relative (grandfather, uncle, older brother, step-father, etc.). While not unheard of, it was atypical (especially before the 20th century) that the mother would be appointed guardian of the child’s estate. Mothers were appointed and could be appointed guardians–but it was not the norm. This was usually done if there was no male relative in the area who qualified as a guardian.
So if the mother is appointed guardian of her child’s interest in an estate ask yourself: “why?” Were there no males in the area who qualified? Keep in mind that guardians had to be of the age of majority and of a character that would be approved by the court.
And if the mother was appointed guardian, make certain you have reviewed the bondsmen on the bond she had to put up. Those men are clues. They likely knew the mother and knew that she would “do right” by the child and their inheritance and would manage it well.