Season 4: Episode 91: The One with Rachel's New Dress
A very pregnant Phoebe is asked to name one of the triplets. Emily offers to show Susan around London. Rachel tries to prepare the perfect evening for herself and Joshua. Emily loves Susan. Phoebe decides that the boy will be named either Chandler or Joey. Joey accidentally tells Chandler he has an awful name. The chick and duck wander over to Rachel's apartment and freak out Joshua, so they go to his parents' house. Ross worries about losing another woman to Susan. Joshua's parents come home unexpectedly. Chandler disowns his name and tries to find himself a new name. The girls convince Ross not to let what happened with Carol happen with Emily. In order to keep Chandler from legally changing his name, Phoebe decides to name the baby Chandler. Chandler reveals to Joey that it was all a trick.