If you listen to U.S. intelligence officials Kim Jong Un is at death’s door. If you listen to South Korean officials, he’s not. If you listen to North Korea, you’ll hear nothing.

The truth is that no one outside of a tiny group of North Korea’s ruling elite knows how ill, if at all, Kim is. But there have been sustained rumors about the dictator’s poor health since last summer, and given how morbidly obese he is and his family’s history of heart disease, it is no surprise that attention is now turning to his successor.

Most of that attention is being put on Kim’s sister, Kim Yo Jong.

Experts who VICE News spoke to are sharply divided about the possibility of Yo Jong becoming Supreme Leader. Some believe it would be impossible for a 32-year-old woman to take control of a country run by an elite group of powerful old men. Others believe she is the natural successor to Kim and that her recent high-profile public engagements show she is being groomed to take control.

Others still say it is impossible to predict what will happen when Kim dies.

But the possibility of a woman taking power in Pyongyang should not be equated with any softening in the country’s stance on foreign policy.

“It is entirely possible that Ms. Kim will prove even more tyrannical than her brother or father or grandfather,” Sung Yoon Lee, a Koreas expert at The Fletcher School at Tufts University, told VICE News. “She will also have to show her mettle by provoking the U.S. with major weapons tests and lethal attacks on South Korea and U.S. forces stationed there.”

Who is Kim Yo Jong?

Born on September 26, 1987, Yo Jong is the fifth and youngest child of former North Korean leader Kim Jong Il. Her mother was Ko Yong Hui, who was the former leader’s second mistress.

Yo Jong was nine when she was sent to Berne in Switzerland, where she attended elementary school. It was here that she forged a close bond with her older brother Kim Jong Un. The pair shared a private home and were attended to by their own chef, housekeeping staff, and bodyguards, according to North Korean Leadership Watch.

Yo Jong returned to North Korea in 2000, having completed the U.S. equivalent of sixth grade. Little is known about her activities in the next few years, but her future as part of her family’s political dynasty was signaled as early as 2002, when her father told foreigners that his youngest daughter was interested in politics and wanted a career in North Korea’s political system.

In 2007 she graduated from Kim Il Sung University in Pyongyang with a computer science degree and joined the ruling Workers’ Party.

She became a close aide to her father after he suffered several strokes in 2008. Over the next few years, she helped plan her brother’s ascension to the position of Supreme Leader in 2011, when her father passed away.

Her brother’s closest aide

Yo Jong has been at her brother’s side throughout his reign, attending many high profile summits, including the two meetings with U.S. President Donald Trump in 2018 and 2019.

She also saw Kim’s ruthless nature up close, including when he ordered the execution of their uncle Jang Song Thaek in 2013 following accusations of corruption, drug use, gambling, womanizing and leading a “dissolute and depraved life.”

South Korea’s intelligence agency reported afterward that Jang was killed by antiaircraft guns and flamethrowers.

She is often seen in photographs wearing an olive green jacket that is normally worn by reporters and photographers that document Kim Jong Un's on-site visits and military field inspections — but her influence on Kim, his public profile, and his interactions with the rest of the world has been huge.

“North Korean media's handling of Kim Yo Jong seems to indicate that she plays a significant role across the gamut of issues, ranging from domestic politics and economy and weapons development to inter-Korean and Sino-DPRK relations,” Joel Wit, director of 38 North and a former State Department officials, told VICE News.

“It remains unclear whether Kim Yo Jong has been involved in shaping and executing Pyongyang's U.S. policy, and if so, how deeply. However, her apparently close involvement in the Kim Jong Un regime's policy-making and policy execution suggests that she will take a similar path to what her brother has taken,” Wit added.

The only black mark on Yo Jong’s career to date was the failure of the second Trump summit, which her brother blamed on her. As a result, he removed her from the ruling party’s powerful politburo — but North Korea’s state media reported last week that she has now been reinstated.

That decision came after several other notable milestones recently that have significantly boosted her official public profile.

Last month, she made her first public statement when she hit out at South Korea, calling it a “frightened dog barking” after the government in Seoul protested against a live-fire military exercise by the North.

Also last month, Yo Jong revealed Trump had sent a letter to her brother. While she praised the U.S. president for his efforts, she warned that the result of the country needed to step up in order to make progress on denuclearization talks.

Can she become Supreme Leader?

While Yo Jong appears to be attaining greater responsibility under her brother, some experts believe that North Korea’s structure means a woman could never take charge.

“North Korea is a Confucian country where seniority and masculinity are respected. Kim Yo Jong is the most trusted ally of Kim Jong Un, but no more than that,” Leonid Petrov, a North Korea specialist and senior lecturer at the International College of Management in Sydney, told VICE News.

Petrov points out that in the case that her brother dies, Yo Jong could be in danger from those who seek to take control, a similar fate suffered by the wife of China’s powerful leader Mao Zedong who held a huge among of power before he died.

“If Kim Jong Un is dead or incapacitated, Kim Yo Jong is likely to repeat the fate of Jiang Qing, also known as Madame Mao, who was imprisoned soon after Mao’s death for her alleged ‘anti-party activities.’”

But others don’t believe the situation is that black and white.

“But even in the era of absolutism, a few women have become sovereigns or top leaders in East Asian countries.”

“It’s not impossible, but the North Korean establishment is a very old-fashioned and sexist one, and having to serve a woman would not be liked by many in the establishment,” Steve Tsang, director of London's SOAS China Institute, told VICE News. “But even in the era of absolutism, a few women have become sovereigns or top leaders in East Asian countries.”

And some experts believe that her recent high profile activities on the international stage, together with her direct bloodline links to the previous leaders make her the obvious candidate.

“She is the natural heir to the throne, as the Kim family regime is more a dynasty than a republic,” Lee said. “One thing Ms. Kim has going for herself and her prospects for regime preservation is that she is a known entity both within and outside North Korea. She has met face to face with Trump, Xi, and Moon. She exudes a softer side of the ruthless tyrannical system that is North Korea.”

Wit is among the most experienced North Korea experts around, having helped negotiate a 1994 agreement with Pyongyang to freeze operation and construction of nuclear reactors suspected of being part of a covert nuclear weapons program.

He says there are a number of possible eventualities when Kim Jong Un does die, including Kim Yo Kong taking over, becoming a figurehead backed by a council of elders, or someone else who isn’t part of the family steps in.

So, with his decades of experience watching North Korea, what is his take on what will happen when Kim Jong Un dies? “I have no idea, honestly,” Wit said.

He then pointed out that the speculation before Kim Jong Un took power proved to be entirely wrong.

“The betting money when Kim Jong Un took over was that he would be a figurehead for a council of elders headed by his Uncle Jang,” he said. “And we know how that turned out.”

Cover: Kim Yo Jong, sister of North Korea's leader Kim Jong Un, attends wreath laying ceremony at Ho Chi Minh Mausoleum in Hanoi, March 2, 2019. (Photo: JORGE SILVA/AFP via Getty Images)