Stella Dalton is the young daughter of Margo Dalton in the episode Need to Know. She was portrayed by actress Elle Fanning. Stella provides the team and Gregory House with insight into her mother's case. The team first gets suspicious when Margo goes through tremendous mood swings when Stella comes to visit and Margo tells her husband (Stella's stepfather Ted Dalton) that she asked him not to bring her to the hospital.