Liza searches online and find the birth certificate and birth name of Nelle, which is Morgan. In retaliation, Nelle searches online and finds Liza's birth name is Debbie. It is a criminal act to access a person's birth or medical records without authorization in the US.
Correcting above comment. Birth names on birth certificates are public record. Ancestry and other genealogy research sites have original birth logs by county scanned in. Details include birth name, birth parents and place of birth. It would not be difficult for a lawyer at that time period to access same information.