Carol goes into labor on the L. With the help of Luka, she makes it into the ER and delivers one twin, Tess, there. She is then moved to the OB and put in the care of OB nurse Abby Lockhart. Dr. Coburn delivers Kate through an emergency c-section but Carol and both babies turn out to be fine. When Mark has to leave Thanksgiving at her house to be Carol's Lamaze coach, Corday is stuck with his father and Rachel. Dr. Dave helps Carter with a diagnosis of a very rare disease.