Abby leaves an infant int the room for a moment, and it disappears from the hospital. After spending the night at her place, Carter is shocked to find out that Rena is a 19-year-old undergraduate. Greene gets his competency results. He and Malucci treat a young boy injecting steroids who is frightened of his father. Legaspi is accused of sexual misconduct by the teenager who caused the train crash, leading Weaver to become concerned that their personal relationship will be exposed.