Kim Jong Un
Kim Jong Un hasn't been sighted lately. Could his sister be North Korea's leader in the meantime -- or in the future? REUTERS

North Korean leader Kim Jong Un has not been seen in public for over a month and speculation about his health has been rampant. The cause of his absence has been rumored to be gout, a cheese allergy or a leg injury, and there are rumblings that his sister, Kim Yo Jong, may be filling in for the leader.

An apparent photo of her, posted by @NorthKoreaNews1 (which is not verified) can be seen below:

So, who is she? Kim Yo Jong seems positioned as the most likely candidate to take over for her brother while he is purportedly recovering. She was born in 1987 and is the youngest of seven known siblings, World.Mic wrote. Even though she is the youngest, she is respected more than some of her siblings who have been disowned from the line of succession.

"Clearly it's an effort to slow-track her into becoming somebody who is important within the system," Victor Cha, an analyst with the Center for Strategic and International Studies, told CNN.

"I can see how it's possible that she's in some sort of temporary position. It's very difficult for the North Korean system to run without one of the Kim family at least titularly in charge. So, if Kim Jong Un is indisposed, she's really the only available body that's left, in terms of a direct Kim family line," Cha added.

As deputy director of the Korean Workers' Party, she has power and influence. And a crucial piece of the puzzle is that she's said to have a strong relationship with her brother.

They were born to the same mistress of former leader Kim Jong Il and grew up together, according to reports. They lived in Pyongyang together, went to the same boarding school in Switzerland and even allegedly performed in a school recital together, Mashable wrote. “She can get [Kim Jong Un] on the telephone, she can see him in person, that kind of thing," North Korea Leadership Watch's Michael Madden told Mashable.

Kim Yo Jung has always had an apparent penchant for politics. "She was one of the only ones that was distinctly interested in politics, in North Korean politics," Madden said. "Kim Jong Un is not a micromanager. It's very possible she could be running a lot more things than we think." NK Leadership Watch revealed she plans Kim’s appearances, itineraries, schedule, logistical needs and security arrangements

Ultimately, even though Kim Yo Jung is still in her 20s, she got the family bloodline and, it seems, her brother's approval and trust. Having a “Kim” in power is important to the country to show stability and confidence, World.Mic wrote.

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