Homesick

S6, E22: A baby boy's poisoning leads detectives to a baby food manufacturer, but the real culprit might be in the family. Poison is found in the nanny's room, leading to her arrest. During the trial, however, Kincaid and McCoy discover that the baby's older half-brother - jealous of the attention paid to the new baby - killed him. Patti Lupone (Life Goes On) guest stars.