Marshall's father, Marvin Sr., dies in How I Met Your Mother season 6 in one of the most emotionally charged episodes of the show. It marks a turning point in Marshall's life, as he's waiting to know whether he and Lily are both fertile and spends the whole episode anticipating bad news. Everything seems to be pointing at one of the happiest moments of the show when Marshall prepares to tell his father he's going to be a dad, but an unanswered call changes everything: Marvin Sr. is dead.
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