‘Cruel’: Why Kim’s sister is a problem
How might a new-look North Korea operate if rumours about Kim Jong-un's ill-health are realised?
As speculation continues about the Supreme Leader's absence from public life - including some suggestions he is in a coma - experts are looking ahead to what comes next.
Some say Kim's sister, 32-year-old Kim Yo-jong, might take control of the hermit kingdom and "rule with an iron fist".
But others say she is too "cruel and unpredictable" even for a country where fear of leadership has been entrenched since early in the Kim dynasty.
"I haven't seen any evidence, any indication of how she might rule, but my speculation - given the reputation and history of the family - is that she would rule with an iron fist," retired US Army Colonel David Maxwell told US newspapers this week.
But Dr Leonid Petrov, a Korean Studies lecturer at the Australian National University, told news.com.au Kim Yo-jong is not leadership material.
"If something bad suddenly happens to Kim Jong-un, a collective leadership composed of the military top brass and party elders is likely to step in and run the country," he said.
"Kim Yo-jong might be too cruel and unpredictable for the North Korean elites to tolerate. They have been living in fear long enough and will not need another despot with new rules of survival."
He said a "fierce power struggle is inevitable" and "if the party and the army need someone to give them legitimacy to rule the DPRK, they might look for a softer (and weaker) figure in the family, such as Mr Kim's uncle, Kim Pyong-il, or Mr Kim's younger brother, Kim Jong-Chol".
But rumours about Kim Yo-jong's position are likely to continue to swirl after South Korea's National Intelligence Service told the country's politicians she was made "de facto second in command".
Chang Song-min, a former aide to late-South Korean president Kim Dae-jung, alleged Kim Jong-un was "in a coma" and Kim Yo-jong was poised to take over.
"A complete succession structure has not been formed, so Kim Yo-jong is being brought to the fore as the vacuum cannot be maintained for a prolonged period," Mr Chang said.
Other Korea watchers think it's unlikely she would take on the role permanently, instead becoming a "regent" ruler until Mr Kim's son could be leader in his own right.
Yoo Ho-yeol, a professor of North Korean Studies at Korea University told Canada's National Post in April that Kim Yo-jong's role would "be limited to a regent at most".
"(There is) not only the male-dominant leadership, but also ordinary people there would resist a female leader," he said.
Of course, all of this depends on the health of Kim, who has been increasingly absent from public life.
Even when he appeared on North Korean TV last week, there was speculation that images of him wearing a white jacket and tortoiseshell glasses were taken from an appearance in Pyongyang in December last year when he was pictured wearing exactly the same outfit.
He was reported to have chaired the snappily titled, sixth plenary meeting of the 7th Central Committee of the Workers' Party of Korea, on August 19.
Images distributed by respected news agency Agence France-Presse (AFP) included a disclaimer to news organisations worldwide that they were supplied by a "third party" via the Korea Central News Agency (KCNA), a mouthpiece of the North Korean Government.
"AFP cannot independently verify the authenticity, location, date and content of this image", it read.
Mr Kim made just seven public appearances during April, May and June this year, a figure way down on his 46 public appearances in 2019.
Dr Petrov told news.com.au Mr Kim was not "getting younger and healthier" … "particularly in the middle of a global pandemic".
Colonel Maxwell, who co-authored the Pentagon's original 1999 contingency plan with South Korea for the collapse of the North's regime, told the New York Post that Mr Kim has failed to live up to expectations he would be "more open to the outside world".
"That hasn't been borne out," he said. "I think we have to assume that every successor is worse than the last."
Originally published as 'Cruel': Why Kim's sister is a problem