I seem to remember Aberforth having had "an unfortunate incident with some goats" or something, and I believe Dumbledore makes a joke about bartenders, implying that Aberforth is the bartender in the Hog's Head.
Do you remember in which of the books DD made the joke? When HP and the DA meet at the Hog's Head, the bartender looks vaguely familiar to Harry.
Not de ja vu. I actually am repeating myself.