It seems like Naughty Dog has been telling porkies because at no point in The Last of Us: Part I's video game or live-action TV series did it mention that It's Always Sunny in Philadelphia's Frank Reynolds had such a big impact on the wider storyline.
But as can clearly be seen in eli_handle_b.wav's latest YouTube video, we can see that Frank was both directly involved in the death of Joel's daughter Sarah, that he helped kill a bunch of Clickers, and that he was arguably more impactful in the rescue of Ellie from the Fireflies than Joel was.
Check out the hilarious video below to see how the iconic sitcom character fits in Naughty Dog's acclaimed post-apocalyptic world.