- Fake American: Three of the four leads-Ryan Reynolds is Canadian, Rachel Weisz is British, and Isla Fisher is Australian.
- Method Acting: Ryan Reynolds and Abigail Breslin attempted to prepare for the movie by spending a day role playing as father and daughter. Unfortunately, they got mobbed at FAO Schwartz and needed to hurry out. Reynolds didn't want to leave empty handed so he grabbed a doll and bought it for Breslin as a gift, only to realize it was extravagantly expensive when he paid for it. Breslin proceeded to call Reynolds a "moron", which was the moment Reynolds really bonded with her after realizing she shared his snarky sense of humor.
Trivia / Definitely, Maybe