Is he actually Peter's ancestor anymore since his real father is a McFinnigan, not a Griffin?
Rule #1 - The show is simply a performance put on each week. We only count what is actually shown on the show and nothing has to make sense in reality. That said, it is not unconcivable that the th two families share a common ancestor giving both sides many similar features. --Buckimion (talk) 11:16, March 13, 2015 (UTC)