Q: How do I index the names when the mother's and grandparent's last names are recorded as given middle names?
A: See 102813 - Basic Indexing Guidelines: Names - Given Name or Surname
Some records contain names that are not easily identified as given names or surnames. Deciding how to index them can be especially difficult if you are not familiar with the naming conventions of the culture that the individual was from.
If you cannot determine which part of the name is the given name and which part is the surname, or if only a single name is listed, do not separate the names into the Given Name and Surname fields. Instead, keep each name in the same order as was written on the record, and type the information in the Given Name field.