Medical experts opine that genes and stress may be responsible for Omar Bin Laden's schizophrenia.
They say that if Omar indeed has schizophrenia, it's no surprise he reported hearing his father Osama Bin Laden's voice.
"A diagnosis of schizophrenia almost always means someone has psychotic symptoms, and the most obvious of those are hallucinations, and the most common abnormal hallucinations are voices," ABC News quoted Dr. Bruce Cohen, professor of psychiatry at Harvard Medical School, as saying.
Schizophrenia is a severe mental illness characterized by hallucinations, delusions, disorganized speech and thinking and is often accompanied by occupational and social dysfunction.
Doctors say it's a complex illness that results from an interaction between genetics and factors in the environment.
They also say that schizophrenia tends to run in families.
Omar's wife, Zeina, told London's Daily Mail newspaper that the family was "psychologically broken," and she blamed her father-in-law for the stress her family is experiencing.
"Extreme stress can increase the risk of schizophrenia," said Cohen.