I was rereading HBP and I noticed that the Auror who goes to the Gaunt household is named Bob Odgen. I wondered whether this person had any relation to the Odgen Firewhiskey. I was just wondering what you all thought.

Yes I thought that too, Despite the way Marvolo Gaunt treated him I imagined Ogden being pureblood(If his abysmal sense of muggle dress is anything to go by ) And Ogdens firewhisky I imagined to be around for years created by an old wizarding family, Bob could have been half blood I suppose, half Ogden, but yes I imagined him to be pureblooded from the family who created the fire whiskey.

Yeah I thought of that also. There's another Ogden in the books too: Tiberius Ogden, the Wizengamot elder who resigned in protest in OotP after Umbridge was made High Inquisitor.

And wasn't there someone meantioned in HBP with a last name which was Ogden? I think he was meantioned around when Harry and slughorns favourites are having the little lunch...