CBS's How I Met Your Mother celebrates New Year's with "Tailgating." After the holiday, Marshall (Jason Segel) visit his father, Marvin's (Bill Fagerbakke), grave to tailgate a Vikings game and tell the story of the most recent New Year's Eve he and his friends celebrated. Lily's (Alyson Hannigan) dad (Chris Elliott) has an unexpected reaction upon learning of his daughter's pregnancy. Ted (Josh Radnor), Barney (Neil Patrick Harris), and Kevin (Kal Penn) open a bar in the apartment. Robin (Cobie Smulders) gets back on the air while covering for a drunk, disgraced, Sandy (Alexis Denisof). And Marshall learns to honor his dad's spirit of generosity.
The framework story, at first, seems unnecessary. Just because the episode airs a couple of days past New Year's Eve doesn't mean that the night needs to be told in flashback. However, upon further reflection, Marshall's story with his dad fits into the larger themes of the episode. There's a parallel between Marshall and Lily's fathers, and how they react or would react to a grandchildren. There's an element, like in Robin's story, of Marshall realizing his proper place in life. Marshall also acts stupidly, like Ted and Barney, by trying to hog his father, when, really, it honors Marvin more to share what he has with others. Thus, it works.
Lily's dad, Mickey, is a strange one. But he does show up when he needs to. With Lily's life falling into place so nicely, it's no wonder that she looks back upon her disappointing childhood as something she'd rather forget. It also ruins her ability to believe, as Marshall discovers when telling her of cool enigmas he thinks might be true, and that he can't wait to share with their child. Assuming that her father has not changed, and cannot be counted on, she doesn't even tell Mickey about her pregnancy until Marshall pushes her. But it's a good thing he does, because Mickey has gotten Lily's message. He needs to step up, and step up he does, driving all night to deliver a stuffed bear. He may still have trouble expressing himself, as evidenced by the phone call, but he will be a better grandpa than he was a dad. Which is a good thing, since the baby's other grandfather will not be around to do the same.