Marshall: I have no idea how to raise a daughter! What if she makes bad choices? I mean, what if she winds up dating some... Oh, God.
[fantasy scene of Marshall's stripper daughter introducing him to her boyfriend:]
Marshall's daughter: Papa, I want you to meet my new boyfriend.
Elderly Barney: Hey, bro. Thanks for making such a hottie. Who's your daddy?
Marshall's daughter: You are, 'cause of all the sex we have.
[Marshall vomits]