Pretty sure I read somewhere that this is what Jason Segal thought as going to happen. To get a more genuine reaction he wasnt told and/or was given an alternate script. This may just be internet lore, but it's very beleivable.I think you were supposed to think it was a countdown to lily saying she's pregnant. Up to and including Lily getting out of the cab, so you get hit with a sack of bricks when she says his dad died.