Smart. History of mental illness, notably paternal grandmother. Bad relationship with father, related to same. Divorced parents. Psychic, especially in ways connected to death- related to mental illness.

Cluster A: Lydias pretend to be dumber than they are. They remember their grandmothers well, and inherit their powers.
Cluster B: Lysanders pride themselves on their intelligence. Their grandmothers left them with painful memories, and their powers come from another source.