Kim Yo-Jong
Kim Yo Jong, sister of North Korean leader Kim Jong Un, attends an opening ceremony of a newly constructed residential complex in Ryomyong street in Pyongyang, North Korea April 13, 2017.Reuters

North Korea's supreme leader Kim Jong Un has promoted his youngest sister Kim Yo Jong to the country's top decision-making body. Kim Yo Jong was named an alternate member of the Workers Party's Politburo, North Korea's official media reported on Sunday.

She is now the second woman from Kim Jong Un's family to join the party, after their aunt Kim Kyong Hui, who had been a member of the decision-making body when Kim Jong Il was alive. Kim Yo Jong's promotion also indicates that she has replaced Kim Kyong Hui.

"Since she is a female, Kim Jong Un likely does not see her as a threat and a challenge to his leadership," Reuters quoted Moon Hong-sik, a research fellow at the Institute for National Security Strategy, as saying. "As the saying goes 'blood is thicker than water,' Kim Jong Un thinks Kim Yo Jong can be trusted."

Who is Kim Yo Jong? Here are a few interesting facts about her:

Born in September 1987, Kim Yo Jong is four years younger than Kim Jong Un. She was rarely seen in public until 2010 when she was first noticed at a Korean Workers' Party event. Later, she made an appearance during the funeral procession of their father in December 2011.

According to reports, she spent her early years with her mother Ko Yong Hui in central Pyongyang before joining her brother in Berne, Switzerland, to attend school. She returned to the country to study computer science at the Kim Il Sung University in Pyongyang.

Kim Yo Jong and Kim Jong Un stayed in a private apartment in Switzerland, and her father used to send North Korean musicians to Switzerland for her entertainment, the North Korea Leadership Watch reported.

She is married to Choe Song, the second son of the country's most powerful officials, and a close confidant of Kim Jong Un. Kim Yo Jong and Choe Song have a child together.

Reports suggest she played an important role in creating Kim Jong Un's image like his grandfather.

"She's helped Kim Jong Un actually craft the popular image that he's promoted for himself which recalls his grandfather Kim Il Sung who was a very gregarious, outgoing fellow," ABC News quoted Peter Hayes from Sydney University's Centre for International Security Studies as saying.