ER: Make of Two Hearts

Carol has to deal with a woman abandoning her adopted HIV-positive daughter, Tatiana who is later placed in a foster home. Carter gets inundated with Valentine cards from people he doesn't know. Kaysen wants Susan to be his Valentine; Mark and Susan reconcile their recent spat; Deb accidentally gets stoned after eating some LSD-laced chocolates belonging to some cheerleaders.Mark talks to Susan about his marriage problems while they go skating. Meanwhile Peter has to come to terms with his mother's worsening condition.