Lily and Marshall test their friends to find out who would make the best godparents to Marvin on How I Met Your Mother. "Who Wants To Be a Godparent" is the fourth episode of the show's eighth season.
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How I Met Your Mother Season 8 Episode 4 Quotes

You smell that? That's the smell of urine that isn't Marvin's.

Marshall

Barney Stinson how may I direct my penis?

Barney