That's what U.S. and Pakistani officials are trying to determine in the wake of reports that Hamza bin Laden hasn't been seen since the May 2 attack by U.S. Navy SEALs.
His unknown whereabouts could cast a shadow over the U.S. victory, since the younger bin Laden is known in some circles as the "crown prince of terror" and has reportedly been groomed since childhood to wage jihad.
Initial reports were that Hamza was killed during the raid, but U.S. officials later corrected themselves to say that the dead son was actually his 22-year-old brother, Khalid.
Citing a source in Islamabad, Britain's "The Telegraph" newspaper reported that the three widows of the elder bin Laden have told Pakistani security officials that at least one of the dead Al-Qaeda leader's rumored sons (he is said to have had as many as 24 children) has not been seen since the raid.
Without naming Hamza, Pakistani officials confirmed to the paper that one person who was living in the high-walled compound is unaccounted for.
Even though he's barely out of his teens (some reports say he's still only 19), Hamza already has a history of involvement with terrorism.
He's said to have appeared in Al-Qaeda propaganda videos since he was 10 years old and was featured on an Islamic extremist website that commemorated the third anniversary of the July 7, 2004, London bombings. In that video appearance, he reportedly read a poem calling for the "destruction" of Britain, France, Denmark, and the United States, saying: "Oh God, reward the fighters. Grant victory to the Taliban over the gangs of infidels."
Hamza was also implicated in the 2007 assassination of Pakistani leader Benazir Bhutto. Before she died, Bhutto reportedly publicly named Hamza as one of the top Al-Qaeda leaders trying to kill her.
Terrorism seems to run in the bin Laden family. Hamza's older brother Saad is also wanted by U.S. officials for alleged participation in terrorist attacks, including the 2002 bombing of a synagogue in Tunisia that killed 19 people. Saad was thought to have died in a 2009 U.S. drone attack in Pakistan, but a spokesman for the Taliban has denied reports of his death.
-- Heather Maher