Osama bin Laden's three wives have reportedly told Pakistani investigators that one of the al Qaeda leader's sons has been missing since the May 1 raid in which his father was killed. Pakistani intelligence officials fear the son in question could be bin Laden's youngest, Hamza. Here, a brief guide to the most notorious of bin Laden's many children:

Who is Hamza bin Laden?
Among bin Laden's closest confidants, Hamza, 19, is "a budding teen terrorist groomed since childhood to wage jihad," says Chuck Bennett in the New York Post. Some experts believe that Hamza, dubbed the "crown prince of terror," was being trained as his father's heir.

Didn't reports say he died in the commando raid?
Initially, yes. One of bin Laden's sons was killed in the raid on the family's hideout in Abbottabad, Pakistan. At first, U.S. officials said it was Hamza, but they later clarified that the dead man was his 22-year-old brother, Khalid.

How certain is Pakistan that he escaped?
Call it an educated guess. Pakistani investigators say that one person who was living in the Abbottabad hideout remains unaccounted for, Hamza's mother was detained, and U.S. commandos did not bring anyone back alive.

Has Hamza been linked to any attacks?
Yes, he was implicated in the assassination of Benazir Bhutto, the moderate Pakistani leader who was killed in a bomb attack during a 2007 campaign rally. Bhutto had publicly named him as the leader of an al Qaeda group plotting to kill her.

What else has he done with al Qaeda?
Hamza has appeared in al Qaeda propaganda videos since age 10, when he read a jihadist poem at his brother's wedding. In 2005, at age 13, he appeared in another video holding an assault rifle, after taking part in a battle with Pakistani forces in tribal territory near the Afghan border. In 2007, he called for the destruction of the U.S. and Britain in a video marking the third anniversary of the London 7/7 bombings. "Oh God, reward the fighters," he said. "Grant victory to the Taliban over the gangs of infidels."

Is Hamza the only bin Laden wanted by the U.S.?
No, his eldest brother, Saad bin Laden, also has been accused of participating in terrorist attacks. Saad was allegedly involved in a 2002 synagogue bombing that killed 19 people in Tunisia, and in the planning of 2003 suicide bombings in Saudi Arabia and Morocco. In 2009, a report said he had been killed by an American drone attack in Pakistan's tribal belt, but a Taliban spokesman said the strike had left Saad uninjured..

Sources: ABC News, Telegraph, NY Post, Daily Beast, Daily Mail, The News