Where's the poop? is the phrase that Lily uses when she realizes that someone is lying or hiding something from her. The phrase is followed by the name of the person she is addressing.
In Unfinished, Robin was trying to hide her difficulties of getting over her break up with Don after seeing him on TV, but Lily said "Where's the poop, Robin?" and explains that when she was a kid she had a dog named Bean and whenever he made a face she knew that he pooped in the house and says that Robin just made the same face when she was lying, in which Robin dubs her a "poop sniffing dog" in which Marshall says "I think that's just called a dog."
In Canning Randy Lily used the phrase again when she asked Robin who she slept with.
|Friends & Family||Marshall Eriksen • Ted Mosby • Robin Scherbatsky • Barney Stinson • Scooter • Mickey Aldrin • Janice Aldrin • Rita Aldrin • Morris Aldrin • Grandma Lois • Marvin W. Eriksen • Daisy Eriksen • Unnamed Eriksen Child|
|Places||MacLaren's Pub • Lily's Kindergarten • Wesleyan University • Marshall and Lily's apartment • Marshall and Lily's house • The Apartment • Lily's first apartment • Lily's second apartment|
|Phrases||Where's the poop? • You sonuvabitch|
|Others||You're dead to me look • Marshpillow • Intervention banner • Lily's bisexuality • Aldrin Justice (punishment)|