SEOUL, South Korea (AP) — North Korean children are already singing the praises of the young man in line to become the reclusive nation's next leader, analysts say, but the rest of the world doesn't even know the age, or, until recently, how to spell the name of Kim Jong Il's youngest son.

Kim Jong Un is expected to make his public debut as the Dear Leader's heir apparent at an upcoming convention of the Workers' Party, North Korea's biggest political gathering in 30 years. If so, it could be the first time the world — and many North Koreans — get a peek at the communist crown prince hidden so long from public view.

Jong Un is said to look like his father, in face and figure, but there's no verifiable photo of him as an adult. The most widely circulated image of him was taken as a boy, a cherubic imp with bright eyes and a cheeky grin.

The man reportedly tapped to take over leadership of the nuclear-armed nation of 24 million is believed to be 27, but the exact year of his birth remains in dispute. Until last year, the South Korean government didn't even know how to spell his name because it's so rarely seen in print and has never been published in North Korean media.

The mystery is typical in reclusive North Korea, which maintains strict control over information and enforces a reverent cult of personality focused on the Kim family. Portraits of national founder Kim Il Sung and son Kim Jong Il grace the walls of every room and pins bearing their images adorn every lapel.

Kim Jong Il was similarly kept out of the public eye until his official debut at the last major political conference in 1980. He succeeded his father when the "Great Leader" died in 1994 of heart failure in what was the communist world's first hereditary transition of power.

Since then, Cuban leader Fidel Castro has handed the reins to his brother, Raul. And there have been other dynastic transfers of power. Former dictator Jean-Claude "Baby Doc" Duvalier of Haiti was named president for life when his father, Francois, "Papa Doc," died. Syrian President Bashar Assad was groomed by his father, Bashar, for years and also took over upon his death.

Now, in North Korea, analysts believe the torch will pass to the third generation, with Jong Un assuming a key Workers' Party position, perhaps becoming the organizational secretary like his father before him, said Cheong Seong-chang, a senior fellow at the Sejong Institute think tank.

But the next leader of the Stalinist state may not have the same benefit of years of grooming. Kim Jong Il reportedly suffered a stroke two years ago and is believed to have diabetes and a kidney ailment. In fact, the political convention — scheduled for "early September" — may have been postponed a few days because of the leader's poor health, said Ha Tae-keung, chief of Open Radio for North Korea, a Seoul-based station specializing in North Korean affairs.

Jong Un is the youngest of Kim's three sons, but signs that he is his father's choice to succeed him began emerging last year.

He's already being hailed as the "Young General" and "Our Commander," and North Koreans are busy learning an ode to him called "Footsteps," analysts said.

The state-run art studio is making portraits and badges bearing Jong Un's image, Open Radio for North Korea said last month, citing sources in the North.

Jong Un is tough and ambitious like his father, according to the memoir of a man who says he who spent 11 years as his sushi chef.

As a graduate of Kim Il Sung Military University, Jong Un has a military education — a key attribute for leading a country operating on a "songun" — "military first" — policy, said analyst Paik Hak-soon, also of the Sejong Institute.

The young son has steadily built his political clout by getting involved in domestic and foreign policy, securing a position in the ruling party as well as head of the State Security Agency that monitors the party elite, said Cheong.

He has also begun playing a leadership role with the military, Cheong said.

"Rather than saying he's won the military's loyalty, it would be more accurate to say he 'seized' military power," he said.

How a young man untested and inexperienced, raised in Europe and now living a cloistered life in Pyongyang will lead a country locked in a standoff over its nuclear ambitions and struggling to feed its people remains an open question.

"On the negative side, he's more aggressive than Kim Jong Il," Cheong said. "But he's more open-minded when it comes to the economy." He could carry out reform and policies encouraging openness.

Experts and media outlets are scrambling to learn what they can about Jong Un, one of three children Kim Jong Il had with dancer Ko Yong Hui.

The chef, who goes by the pen name Kenji Fujimoto, has described Jong Un as a competitive, even ruthless, child.

Dressed in a military outfit, the young Jong Un "glared at me with a menacing look when we shook hands" the first time they met, Fujimoto wrote in "Kim Jong Il's Chef." ''I can never forget the look in his eyes which seemed to be saying, 'This one is a despicable Japanese.'"

He recalled a 12-year-old Jong Un blowing up when his sister addressed him as "little older brother." He preferred "top comrade." He hated to lose and berated teammates who faltered on the basketball court.

But he also had a surprising sensitive streak, Fujimoto writes. After Fujimoto mentioned running out of beer, Jong Un turned up one day with two bottles of Heineken stuffed in his pockets — a gesture that brought the chef to tears.

Basketball was his chief passion, especially following the Chicago Bulls, the chef recalled. He also loved movies, just like his dad. In looks, tastes and personality, the youngest son was the "spitting image" of his father, and it was clear even back then he was the leader's favorite, he said.

During his middle school years, Jong Un and his brother Jong Chol were shuttled off to Switzerland, the younger one reportedly enrolled under the name "Pak Un," a name combining his middle name and an uncle's surname.

Authorities at the Liebefeld-Steinhoelzi school near Bern confirmed last year that a North Korean youth studied there in the late 1990s but declined to give his name.

"The pupil was well integrated, industrious and ambitious," town education director Ueli Studer said in a statement to The Associated Press. "His hobby was basketball," and he spoke English, German and French.

Desperate to claim the first photo of the future leader as an adult, Japan's TV Asahi last year published a picture of a man it said was Jong Un, complete with paunch, perm and sunglasses like the ones his father famously sports.

It turns out the photo was of a 40-year-old South Korean construction worker who posted the snap online, joking at his own resemblance to the North Korean leader.


Associated Press writer Kwang-tae Kim contributed to this report.