Kim Jong-un's sister Kim Yo-jong could be the next to lead North Korea, here's all you need to know about her

Reports broke this Monday that North Korea's leader Kim Jong-un is in "grave danger" following heart surgery. As United States officials closely monitor the situation, all eyes are on Kim Yo-jong, Kim Jong-un's sister, who has been slowly rising in ranks beside him. 

On April 20, CNN reported on Kim Jong-un's medical condition, who had reportedly undergone a cardiovascular system procedure over "excessive smoking, obesity, and overwork" on April 12. According to CNN, US officials are monitoring intelligence on the North Korean leader, with one suggesting that the concerns about Kim's health are credible but the severity is hard to assess.

However, all attention has now turned to Kim Yo-jong, Kim Jong-un's younger sister, who gave her first public statement earlier this year in March when she condemned South Korea as a “frightened dog barking” after Seoul protested against a live-fire military exercise by the North.

In January, she was named as a first vice-department director of the central committee of the ruling Workers' Party of Korea, her political statement in March indicated that she had made a clear rise in the hierarchy according to analysts.

According to Go Myong-hyun, an analyst at the Asan Institute for Policy Studies, who spoke to The Guardian, "By having someone like Kim Yo-jong – who has been a dovish figure towards the South and acting as a soft and friendly messenger – issue such a strong statement condemning the current government, the North is raising its pressure."

However, Kim Jong-un's sister's political rise could have been years in the making. The brother and sister have a closed relationship ever since they shared isolated years while studying together in Switzerland from 1996 to 2000, and in North Korea, "where social and emotional isolation appears to have been a defining force in their early lives."

Kim Yo-jong has been one of her brother's closest advisors and even acted as her brother's envoy to South Korea during the Pyeongchang Winter Olympics in 2018. She is also reportedly the driving force behind creating her brother's cult of personality, which is supposedly modeled after that of their grandfather, Kim Il-sung, who founded North Korea.

Yo-jong suffered a minor setback to her political career when she was removed from the position in the politburo and was told to keep a low profile following the failure of the Hanoi denuclearization summit with the United States. However, she was reinstated earlier this year and was promoted to vice-minister for foreign affairs.

Not much is known about Yo-jong's personal life. While it was reported in 2015 that she had married Choe Song, the second son of government official Choe Ryong-hae, South Korean government sources denied the accuracy of the reports. 

It was reported later in the same year that she was expecting a child in May. The father, who was not identified, is speculated to be either a fellow alumnus of Kim Il-sung University  (where she studied computer science), an official in the Workers' Party of Korea or a member of the military unit responsible for guarding her brother.

Leonid Petrov, a North Korea specialist and senior lecturer at the International College of Management in Sydney, told The Guardian that Kim Yo-jong has a strong influence on her brother. Petrov said, “She is not associated with his purges or military brinkmanship, but knows all about them. She is a trusted political figure who helps Kim maintain a positive public image when he is dealing with foreigners or South Koreans.”

However, Petrov thinks it is unlikely she will take over her brother's role, despite knowing how to smoothen his initiatives and strengthen his soft power. Petrov said, "North Korea is a Confucian country where seniority and masculinity are respected. She is Kim’s most trusted ally, but no more than that.”

If not Kim Yo-jong, then who will take over North Korea? Experts point to Choe Ryong-hae, her supposed father-in-law who is the Chairman of the Organization and Guidance Department. Either way, it looks like Kim Yo-jong will have an important role to play long into North Korea's and the world's future.