KIM Jong-un has a secret son - but is embarrassed to show him in public because he is "not fat enough".
The bombshell claim was made by Choe Su-yong, a retired official from the National Intelligence Service (NIS) in neighbouring South Korea.
He alleged that the lad's "unappealing physical appearance seems to have discouraged Kim from disclosing his son in public".
"Unlike his father, or his sister who is plump and well-fed, Kim's son is said to be pale and thin," Su-yong told the Korea Times.
He added: "I heard that his son doesn't look like his great-grandfather, Kim Il-sung, at all."
For North Korean leaders, a resemblance to Kim Il-sung - the nation's chubby founder - is thought to be a must-have attribute.
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The current leader has been accused of playing up his resemblance to Kim Il-sung, his grandfather, in a bid to bolster his own legitimacy.
And there may be more chubby North Korean leaders to come, such as Kim Jong-un's "plump" daughter, Kim Ju-ae.
Born and bred to likely take over his despotic reign over North Korea - Kim Jong-un's Gucci-loving daughter is becoming a spitting image of her father.
Home-schooled, horse-loving, ski-obsessed Ju-ae first appeared on the scene at the end of 2022, walking hand in hand with her father to gleefully watch a ballistic missile test.
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While there are no images of the mystery secret son, there are pictures of a young Kim Jong-un when he was heir to the North Korean leadership.
A handful of photos have emerged showing the trim tyrant before he ballooned to his present size.
But experts think we can visualise him simply by looking at a younger Kim Jong-un - who himself used to be skinny.
Michael Madden, founder of North Korea Leadership Watch, said: "When Kim Jong-un was the hereditary successor, he was actually thin.
"You go back and see those pictures. He was a thinner dude.
"His father and his aunt told him that he needed to gain weight so that he could project authority.
"So that when those North Korean elites, especially those old generals, saw this 27/28-year-old guy, they would feel physically intimidated by him."
Mr Madden - a fellow of the Stimson Center in Washington DC - said this preference for plus-sized leaders also had a historical basis.
He said: "There's some Korean concepts about how we present ourselves to other people, and there is a certain idea about attraction and attractability.
"The definition of what is considered attractive and pleasant-looking is going to differ far from something we would see in the west.
"When we see Kim Jong-un, when we see his father - we see his grandfather, right? Chubby cheeks, right? Rosie chubby cheeks, smile on the face.
"Being thin and austere is going to remind the North Korean population that almost a million people starved to death during the late 1990s."
The NIS believes Kim Jong-un has three kids - the son is the oldest, followed by Kim Ju-ae, and then a child of unknown gender.
Choe agrees that the eldest is a son, but believes the dictator has only two legitimate children - this unnamed son and Kim Ju-ae - plus two kids born out of wedlock.
For Mr Madden, the question of which child ultimately ascends to power is still unanswered.
He highlighted the example of Kim Jong-un, who bulked up before claiming the top job.
He said: "That's what would happen with a pale and thin Kim kid, is he's going to be told to gain weight and get some sunshine.
"It worked out for the current leader."
North Korea has a form of passing over the first-born and giving the leadership to a younger sibling.
Kim Jong-un was picked over his big brother, Kim Jong-chul, who his father reportedly deemed "no good because he is like a little girl".
And though North Korea has never had a female leader, Mr Madden thinks that's not necessarily an obstacle to Kim Ju-ae.
He said: "If Kim Jong-un decides that his daughter is going to be hereditary successor… the last time I checked, North Korea is a dictatorship.
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"So when the leader says go, we go, right?
"Good luck standing up and opposing that when that happens."