A major crisis arises for Pratt (Mekhi Phifer) and Harkins (Leslie Bibb) as they care for an injured teenager who is harboring a secret from her father. Kovac (Goran Visnjic) has an eye-opening encounter with an elderly female patient. Chen (Ming-Na) reacts strangely when an abandoned baby turns up in the ER. And Abby (Maura Tierney) is shocked to discover that her bipolar mother, Maggie (Sally Field), wants to stop treatment for Abby's similarly bipolar brother, Eric (Tom Everett Scott). ~ Hal Erickson, Rovi