When Aedelas was a child, many years before the foundation of the Alliance of Lordaeron, Aedelyn was tried and convicted of selling state secrets (to whom, it was not mentioned), and presumably executed. Aedelyn's treachery was a stain on Aedelas' future career during the Second War, a career fuelled by consumption of alcohol. Despite being the "son of a traitor", the younger Blackmoore earned himself the rank of Lieutenant General, and the position of overseer of the internment camps holding the captive orcs, for his service.
Upon suggesting a surprise inspection of Durnholde Keep to his father, King Terenas, Prince Arthas Menethil wished to make certain that Aedelas was not hoarding the funds for the camps' maintenance, and that he would not go the route of his father (which, of course, he eventually did). ( )