General Monger (uncle)
B.O.B.'s Big Break (mentioned)
Dr. Cockroach precedes to throw bits of B.O.B. at Captain Monger, to which he replies that Dr. Cockroach throws like his 12 year old niece.
In the episode Night of the Living Dog, Monger confirms that he has more than one Niece and Nephews, and he was the one on doody duty with their pets. Judging by his voice, it seems they're very irresponsible owners.