S2, E14: Dr. Kelso (Ken Jenkins) assigns J.D. (Zach Braff) to work on a patient with Dr.Townshend (Dick Van Dyke, "Diagnosis Murder") -- his longtime friend and colleague -- but things go downhill when Dr. Townshend insists on using his "old school" treatment method which proves to be an alien concept to an inept J.D. While Kelso defends his friend's technique, Dr. Townshend's lack of current medical knowledge forces Kelso to admit his mistake. Meanwhile, Carla (Judy Reyes) tells Turk (Donald Faison) she needs time to consider his proposal because she thinks he is still too immature, prompting Turk to invite his married brother (D.L. Hughley, "The Hughleys") for a visit to show Carla how seriously he is. In addition, Elliot (Sarah Chalke) learns the sex of Jordan's (guest star Christa Miller Lawrence) baby, but Dr. Cox (John C. McGinley) and his ex-wife can't agree if they want to know.