" Researching only the patronymic line misses half the story. It’s not always about the name of the father. Unlike Muggle Britain, what we see of wizarding Britain in these seven books indicates that all wives take their husbands’ surnames (and all the marriages we see are between a woman and a man). The mother’s name can be obscured within a generation, as we see with Merope Gaunt, who named her son after her father and her husband, eliding her own identity as completely as she could. Yet the key to understanding Voldemort in this volume has been his mother’s story. The mother’s name and story are key to understanding Snape. The author is using loud silence to tell the reader that the missing story of Harry’s mother will turn out to be key, as well. "

― Lorrie Kim , Snape: A Definitive Reading