What is it like to have Osama Bin Laden as your father?

How can you ask such a thing of your son? Author Jean Sasson

New book Growing Up Bin Laden describes the upbringing of Omar Bin Laden, who fled from his father during the Afghan war.

"The shocking thing is how normal Omar is," says the book's author Jean Sasson.

She describes Omar as an "empathetic man" who was unable to grant his father's wishes to following his footsteps.

Ms Sasson told the Today programme that Osama had called upon his young sons to be martyrs and fight for Jihad.

That is when, she said, Omar realised "the heart sickening reality that his father hated his enemies more than he loved his sons."

"Omar cares for other people. When you have that sensitivity, you can't go out and murder other people," she says.

"He wants to do the opposite of what his father is doing, and convince people that violence is never the answer to disagreements."