North Korean leader Kim Jong-il's best-known sons -- his eldest Jong-nam and his third son and heir Jong-un -- barely know each other, sources say.
A South Korean government source on Thursday said the conclusion was drawn from the time the two spent at school or living abroad and from intelligence reports. "They've hardly met," the source added.
Jong-nam, who was born in 1971, was at school in Switzerland when his younger half brother Jong-un was born in 1983 or 1984. In 1980, Jong-nam left for Moscow with his mother Song Hye-rim and stayed in the Soviet Union and Switzerland until the late 1980s. Song died in 2002.
Kenji Fujimoto, Kim Jong-il's Japanese cook between 1987 and 2001, said in a recent interview he never met Kim Jong-nam in person but lived with Kim senior's second and third sons Jong-chol and Jong-un, who were born of the same mother.
Kim Jong-un went to school in Bern, Switzerland between 1993 and 1998. Kim Jong-nam has lived in virtual exile in Macau and Beijing since he was effectively expelled from Pyongyang after he was caught attempting to enter Japan on a forged passport in 2001.
A North Korean source said when Kim Jong-nam returned in Pyongyang after his father had a stroke in August 2008, "we paid attention to whether all three brothers would get together, but it seems Jong-un and Jong-chol were separately staying at Kim Jong-il's villa in Wonsan and a guest house near Pyongyang and didn't get a chance to meet Jong-nam."
"There can't be much brotherly love between them, so nobody knows what'll happen when their father dies," the source added.
Rumors have been circulating since last year that Kim Jong-un's aides attempted to assassinate Jong-nam.