there's some insinuation that Hal's biological father could be the medical attache: -- Hal's "atavistically dark-complected” -- they share an interest in byzantine erotica -- from what i remember, dates and ages line up correctly to put Avril and attache both attending Brandeis a yearish before Hal is born -- there's a reference or two to James finding that specific affair particularly upsetting -- Avril's said to have a preference for sleeping with Canadians -- the attache is "one-half ethnic Arab and a Canadian by birth and residence"

so Hal could potentially be 1/4 "near-eastern"