Adeline's half-sister. Adeline admires Susan's ability to escape their mother's harsh demanding rule. Susan marries well and becomes a socialite who moves in the same social circles as her mother, though her mother doesn't recognize Susan when they encounter each other. Susan is the only one of the children who understand Adeline's feelings of abandonment upon Jeanne's death, which is important to Adeline because Susan herself has also been disowned.