Officially, in the Democratic People's Republic of Korea, or DPRK, there are four important members of the Kim family: North Korean founding father and president Kim Il-sung, his first wife Kim Jong-suk, who died in 1949, their son and late leader Kim Jong-il, and his son and current leader Kim Jong-un.

The February 13 killing of Kim Jong-nam highlights a series of complicated family connections, common-law wives, in-laws, extended family members and personal and political rivalries.

The well-appointed and opulent houses in North Korea's elite residential subdivisions can be loud and crowded places, inhabited by squabbling family members competing for attention, money, power and prestige. A purged and executed uncle and the murder of a rebellious half-brother are just a very jagged tip of an immense iceberg.

The favoured bloodline of the revolutionary family

The supreme leader

Kim Jong-un, 33. The current supreme leader's uncanny likeness to his grandfather dazzled the North Korean old guard elites. It is not, as some have alleged, the result of plastic surgery.

Having some of his father's personality traits, particularly a hair-trigger temper and Manichean worldview, Jong-un established himself early as "a darling heart boy" of North Korea's senior general who supervised his education and grooming.

Unlike his brooding more introverted father, Jong-un also inherited some of his mother's more extroverted and gregarious traits. Whereas his father kept many of his public interactions formal and stiff, Jong-un is more than happy to glad-hand and hug the North Korean citizens he meets.

Jong-un's personality seems at times to be a toxic mix. It is very useful to keep your underlings guessing when running the country's internal affairs, but when those personality treats leak outside in the form of the very public purging and execution of an uncle, or the alleged murder of a half-brother, observers in the international community can be forgiven for feeling uneasy.

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Kim Jong-un's siblings:

The favourite daughters

Kim Sul-song, 42. Of Jong-il's five common-law wives, only one was recognised as legitimate by his father.

Kim Yong-suk was considered the "official" wife, and was the result of matchmaking by Il-sung.

The couple had two daughters, one of whom was Kim Sul-song - the favourite and most favoured of the late leader's seven children.

A polyglot and intellectual, Sul-song worked closely with her father and grandfather. For a number of years, she managed Jong-il's public schedule, travel itineraries and security arrangements. The late leader once proudly boasted of his daughter's political skills to a foreign ambassador

Since the late 2000s she has become a hidden, but significant power player in palace politics and owns several large trading corporations. The nature of the relationship between Sul-song and Jong-un is not fully known, but she is a critical player in the regime.

If something should happen to Jong-un, she is a likely candidate to succeed him.

Kim Yo-jong, 29. Jong-il's youngest child is one of Jong-un's closest aides. Like her older half-sister, Sul-song, Yo-jong was a favourite child and expressed an early interest in North Korean politics.

Yo-jong's official position is as a deputy director in the regime's state media and cultural affairs, but she is also responsible for managing her brother's schedule, meetings and bodyguards. Yo-jong will be a power player in the DPRK for a long time to come as her career is just getting started.

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The semi-secret brother

Kim Jong-nam, 45; deceased. Jong-nam was Jong-il's eldest son, the result of his relationship with the South Korean-born actress Song Hye-rim.

Jong-nam grew up mainly with his mother's intellectual family in secret, while his father consolidated his power base.

He lived outside North Korea, on and off for 10 years, going to school in Switzerland and Russia. When Jong-nam returned to the DPRK, he was listless, and despised being kept behind the palace walls. He also started expressing his qualms about North Korea's political system to his father. He would eventually start working in the regime - holding positions in the national police and helping to set up the country's IT.

There have always been mixed signals as to whether Jong-nam would actually be his father's successor.

In any event, Jong-il deemed him more useful to his interests if he operated outside the DPRK as an expatriate. Jong-nam managed some of the Kim family's accounts and performed a number of sensitive tasks as one of his father's personal emissaries. Jong-nam was fairly outspoken in his opposition to a third generation hereditary succession.

In his will, Jong-il instructed that Jong-nam not be targeted for assassination by his half-brother's supporters.

Another half-brother

Kim Jong-chol, 35. The eldest son of Jong-il's marriage to his beloved fourth wife Ko Yong-hui has very little interest in family or regime politics.

Jong-chol has always had the same interests as his father, specifically music, films - he mostly likes anime - and writing.

He holds a nominal position as a contributing writer to the regime's official publications. But Jong-chol's passion and interest is electric guitars and American blues and rock music with a particular and well-documented affection for Eric Clapton.

Jong-chol, like other members of the family, has been the subject of misleading information. It is not that his father explicitly said that Jong-chol was "girlish", but that he did not have the personality suited for North Korean politics.

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A once powerful lady

Kim Kyong-hui, 70. The daughter of Il-sung's first marriage, Madame Kim was Jong-il's youngest sister and his closest and most trusted relative, confidante and aide.

She was married to Jang Song-thaek, the uncle notoriously executed in 2013, but had been estranged from him since the 1980s. She also had close ties to the murdered Jong-nam.

Separated from her husband, Madame Kim was a powerful force in DPRK politics, entrusted with sensitive regime business and the only person with direct personal access to her brother. She was present when Jong-il passed away in 2011 and was the executor of his will.

She helped shepherd and support her nephew as he settled into the supreme leader's role, even if she had personal misgivings about his preparedness to assume that position. A combination of health setbacks and disillusionment has rendered her politically inactive. She hasn't been seen in public since 2013.

The other Kims

Kim Yong-ju, 95. He is the youngest brother of Il-sung.

For many years during the 1960s and 1970s he led the powerful Organisation Guidance Department where he supervised the work of his nephew, Jong-il.

Some thought, with little evidence, that Yong-ju would succeed his older brother on an interim basis.

Chronic stress-related health problems and outmanoeuvring by Jong Il sidelined Yong-ju who would disappear from public view until the early 1990s. He is one of North Korea's honorary vice presidents, retains a small patronage network and appears occasionally in the country's state media.

Kim Pyong-il, 62. During the 1970s, Jong-il was involved in a legitimate power struggle to become his father's hereditary successor. His father had a second wife with three children of her own.

The eldest son, Pyong-il, studied at a military academy, had more personal popularity than his older half brother and worked as one of his father's bodyguards. What is more, his mother, Kim Sung-ae, was the country's first lady and installed her own family members into the power structure to provide the support and push the succession claim for her son. It didn't work.

Jong-il and his supporters ensured his dominance of the DPRK political culture. Pyong-il would be effectively exiled from the country to a series of diplomatic posts starting in the 1980s. He is currently the North Korean ambassador in the Czech Republic.

The views expressed in this article are the author's own and do not necessarily reflect Al Jazeera's editorial policy.