"Sleepless in Chicago" is the eighteenth episode of the first season of ER. It first aired on NBC on Februart 23, 1995. It was written by Paul Manning and directed by Christopher Chulack. It has Mark Greene learn that his wife wants a divorce. Carol Hathaway past comes back to haunt her when she may not be able to adopt Tatiana. Tired Peter Benton falls asleep while taking care of his mother which leads to an accident.