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Kim Yo Jong has been a key aide to her brother since he became North Korean leader

Russian lawmaker says Pyongyang may test a long-range missile in coming days

NEW: Analyst says appointment shows Kim wants to extend power of family dynasty

(CNN) —

North Korean leader Kim Jong Un’s younger sister Kim Yo Jong was promoted Saturday at a key meeting of the country’s ruling party, state media reported.

Kim Yo Jong’s profile has been rising since 2014, when she was made deputy director of the Propaganda and Agitation Department of the Workers’ Party. She and Kim Jong Un were born to the same mother, Ko Yong Hui.

Like most members of the Kim clan, little is definitively known about Kim Yo Jong beyond her official rank. According to NK Leadership Watch, she is a close aide of her brother’s “and since his accession manages his public events, itineraries and logistical needs, among other tasks.”

Kim Yo Jong was selected as an alternate member of the Political Bureau of the Central Committee of the Worker’s Party at the Second Plenum of the party’s 7th Central Committee.

Also in the reshuffle, according to state news agency KCNA, North Korean Foreign Minister Ri Yong Ho was selected as a member of the Politburo and Choe Ryong Hae, vice chairman of the Worker’s Party and a close aide to Kim Jong Un, was appointed to the party’s Central Military Commission.

Duyeon Kim, an analyst at the Korean Peninsula Future Forum, told CNN Kim’s promotion of his sister “shows that he trusts her and that she is absolutely loyal to her brother.”

“The whole slate of appointments and promotions he has made during the past meeting also shows that Kim Jong Un is trying to turn the Workers’ Party into his party, into a Kim Jong Un party by filling senior positions and key positions with his people,” she added.

PHOTO: KCNA via Getty Images

Kim Yo Jong, the youngest sister of North Korean leader Kim Jong Un, seen in March 2014.

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The Politburo is the North Korean regime’s top decision-making body, led by Kim Jong Un.

According to NK Leadership Watch, a project of The US-Korea Institute, members and alternate members of the politburo can take part in debates and meetings, but only full members can vote.

A recent major decision by the Politburo was the expulsion in December 2013 of Kim’s uncle and high-ranking party member Jang Song Thaek, who was later executed for treason.

Born in 1987, Kim Yo Jong studied in Switzerland like her brother and is believed to have attended Kim Il Sung University and a western European school for her higher education.

“Since her brother’s accession to the supreme leadership of (North Korea), Kim Yo Jong has been routinely observed attending Kim Jong Un’s public appearances,” NK Leadership Watch said.

Her position is such that, according to a Seoul-based think tank run by North Korean defectors, Kim Yo Jong briefly took charge of the country while her brother was reportedly ill with gout or diabetes in late 2014.

Duyeon Kim said the continued promotion of his sister showed North Korea’s leader was “trying to extend power and run the regime like a family dynasty, just like his father, just like his grandfather.”

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