Inside Kim Jong Un's secretive childhood and family

• Kim Jong Un's recent disappearance from public view fueled speculation over the state of his health.
• While the reason for Kim's disappearance remains unconfirmed, the reports about his rumored ill health raised questions about who would succeed him as the leader of North Korea.
• Kim Jong Un has a complicated family tree, as well as a difficult history with relatives.
• Here's everything we know about the supreme leader of North Korea, from a childhood spent attending boarding school in Switzerland to a lifelong admiration for American basketball player Dennis Rodman.

Following is a transcript of the video.

Narrator: Kim Jong Un has been the supreme leader of North Korea since December 2011, but despite how often Kim makes the news, you probably don't know that much about him. Since its founding in 1948, the Democratic People's Republic of Korea's totalitarian government has heavily restricted the information that comes in and out of the country.

However, Kim's life is not a complete mystery. We know most of Kim's childhood was spent hidden from the public eye in Switzerland. He's a fan of former NBA player Dennis Rodman, married to one of North Korea's cheerleaders, and calls his relationship with US President Donald Trump "special." Here's everything we know about Kim's mysterious life and family.

Kim Jong Un is believed to have been born in the early 1980s to Kim Jong Il and Ko Yong Hui. His birth year remains unconfirmed by the North Korean government, which is a contrast to how his father and grandfather's birthdays are celebrated as national holidays. Kim first lived with his mother in the capital city of Pyongyang with the other North Korean elite, but later, Kim was sent to live in Switzerland. Even though the Kim regime doesn't allow North Korean citizens to leave the country, or even travel within North Korea without permission, members of its own family have enjoyed luxurious lives abroad.

In Bern, Switzerland, the family lived in apartments purchased by the North Korean government for roughly $4 million. The Kim family's photo album shows Kim Jong Un doing everything from visiting Disneyland Paris to skiing in the Swiss Alps, and when he wasn't jet-setting around Europe, the future North Korean leader attended the International School of Berne, a private English-language school that costs more than $20,000 a year. Known to his classmates as Pac Un, Kim Jong Un was reportedly obsessed with basketball. In Bern, Kim seemed to wear only Adidas tracksuits and Nike sneakers.

Kim's time in Switzerland ended in 2001, when his father ordered his return to North Korea. Once he was back, Kim started attending Kim Il Sung Military University with his older brother Kim Jong Chol. Although his father, Kim Jong Il, hadn't formally declared an heir, Kim Jong Un was widely seen as his successor. Kim Jong Il reportedly thought that his second-oldest son, Kim Jong Chol, was "effeminate" and weak. Meanwhile, his oldest son and Kim Jong Un's half-brother, Kim Jong Nam, found life in North Korea oppressive.

Kim Jong Un was quickly promoted up the political and military ladder, despite lacking major military experience. The BBC reported that he was made a four-star general, deputy chairman of the power-wielding Central Military Commission of the Workers' Party, and a member of the policy-making Central Committee. In 2011, after the death of his father, Kim Jong Un became the third-generation supreme leader of the Democratic People's Republic of Korea.

In 2012, North Korean media announced that Kim had married a woman named Ri Sol Ju. Not much is known about Ri, other than that she's a former cheerleader and singer in North Korea's famous "Army of Beauties." They are believed to have three children, though their ages and gender have been kept a secret.

During the early years of Kim's reign, it was believed that his aunt and uncle were the real decision makers. His aunt Kim Kyong Hui and her husband, Jang Song Thaek, were trusted advisers who had served on various government committees for years. However, in 2013, Kim ordered the execution of his uncle and his uncle's inner circle. Kim's rocky start as supreme leader continued as he pushed for North Korea to increase its nuclear arms program in 2013. In just six years, Kim Jong Un had conducted more nuclear tests than both his father and his grandfather combined.

Then, in February 2017, international condemnation towards North Korea increased when Kim Jong Un's half-brother, Kim Jong Nam, was attacked at Kuala Lumpur International Airport in Malaysia and later died en route to the hospital. South Korean and US officials speculated that Kim Jong Un ordered the assassination of his half-brother, and Kim Jong Nam's death only served to heighten the world's suspicion of North Korea's leadership.

Donald Trump: I say to the North, do not underestimate us, and do not try us.

Narrator: Over in the US, after taking office, President Trump broke the previous administration's "strategic patience" approach towards North Korea and demanded immediate denuclearization. Kim Jong Un responded by trying to test a nuclear missile at the same time Vice President Mike Pence was scheduled to be visiting South Korea. North Korea continued testing nuclear weapons, while Trump took to Twitter to taunt Kim. Kim responded with his own insults, and as the two leaders continued sniping at each other, odds of war between the two countries seemed to increase. But then 2018 changed everything.

That March, Kim Jong Un made a secret trip to Beijing, his first known trip outside North Korea since coming into power. Just one month later, Kim made history when he met with South Korean President Moon Jae-in, becoming the first North Korean leader to set foot in South Korea in 65 years. Later that summer, Kim met with Trump in Singapore. It was the first meeting between a North Korean leader and an sitting US president. Kim went on to call his relationship with Trump "special."

As of April 2020, it appears Kim's health may be less than optimal, and rumors are circulating that he may have had surgery. Kim wasn't seen at his grandfather's birthday celebration on April 15, which is abnormal, considering it's North Korea's most important holiday. There's no way to know for sure why Kim hasn't been seen, but there are reasons to believe it's health-related. Back in 2008, his father wasn't seen at an important parade. It was later revealed that his father had had a stroke, so it wouldn't be the first time a North Korean leader missed an important event due to health concerns.

Kim's been reported to have health issues as early as 2014, when he disappeared from public view for 40 days. He returned limping and using a cane to walk. However, Kim could just be staying away from the public to protect himself from COVID-19, even though North Korea's been saying it has zero confirmed cases of the virus in the country, something public health experts find hard to believe.

Regardless of the reason why Kim has been MIA, the mystery around his health has brought other questions to the forefront, like who will succeed him? His kids are too young, his brother seems unlikely, and though his sister, Kim Yo Jong, holds a political title, there has never been a female leader of North Korea, and that's unlikely to change anytime soon.

There's also the critical question of what could happen to North Korea's nuclear arsenal. The US has previously made offers to help rebuild North Korea's weak economy if its government hands over its nuclear weapons, but we'll have to wait to find out if North Korea will take the US up on its offer.