Earlier this week, the football world lost an icon with the passing of former Super Bowl-winning defensive coordinator Buddy Ryan, whose funeral will be held Friday. From the moment his passing was announced, the tributes rolled in, from Mike Ditka to Cris Carter.

Of course, no one took the news harder than Ryan's own sons, current Bills head coach Rex Ryan and his brother Rob, the defensive coordinator in Buffalo.

Earlier in the week, Ryan called Buddy "his hero" and on Thursday he expanded on his father's final few days to Sports Illustrated.

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According to Rex, they weren't easy.

"It was a surprise in the fact that we thought he was doing a lot better," Rex said Tuesday evening, while he and his wife, Micki, were driving to Kentucky. "But he had faced everything. He had just been diagnosed with Parkinson's Disease; all those bouts of cancer he has had; numerous strokes; congestive heart failure. He actually beat encephalitis before. He eventually just couldn't take it -- €”I guess, with all that stuff piling up, it just got him. And you know what, the one thing that is amazing is, he couldn't hear, he could barely talk at the end, his teeth were falling out from all the radiation, he broke his back like three different times -- €”and he never complained one time. Not one time. He was one tough sonofagun."

From there, Rex continued, explaining how important this season is to him, not only in terms of his long-term career prospects, but also in honoring his late father.

"This season means a hell of a lot to us. Our name, our legacy, means a hell of a lot," Rex says. "Our dad is recognized as being one of the great defensive coaches, probably arguably the best, in the history of the game. You can't say he's not in the top five, certainly. And we've been pretty successful through the years ourselves, but nothing like we want to be.

We have won five Super Bowls as a family, but we want to win our sixth at some point. And I want to win it as a head coach, because that has never been done in our family. Obviously, it's not like these teams are going to roll down for us. We have to earn everything we get, and we're a long-ass way away from it. It's going to take a ton of work. But I really like my team."