Speaking in Filipino, the man, 48, revealed how all these years he had been bullied by his elder half-brother. “I always gave way. But there’s a limit. Now I have to stand for my principles.”

Aired on national radio last week, the line could have been lifted straight out of a daytime melodrama, a baring of what Filipinos call sama ng loob, hidden resentment. However, the character showing his anger was one of the country’s most powerful men: Senator JV Ejercito, son of disgraced ex-president Joseph “Erap” Estrada.

Ejercito was telling a news programme why he was running for re-election in May next year, pitting him against his half-brother, the former senator Jose “Jinggoy” Ejercito, 55. There is no love lost between the two. According to Jinggoy, “we’re not on speaking terms”. He has his own grounds for resentment: in 2014, when both were senators, Ejercito signed a Blue Ribbon Committee report that identified several colleagues implicated in the theft of billions of pesos in development (“pork barrel”) funds. Jinggoy Estrada was one of them. He was arrested and spent three years in detention before he was allowed to post bail last year. Ejercito himself was charged with corruption when he was mayor. He was acquitted last year.

Jinggoy is Erap’s son by his wife, Ejercito by a common-law wife. Both children served as mayors and senators, Ejercito having been a congressman to boot.

The 81-year old Erap himself started as a mayor, then became senator, vice-president, president and is now back to being mayor of Manila, where he is running for re-election. His wife has been a senator, his common-law partner (Ejercito’s mother) is currently a mayor.

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The Estrada family’s octopus-like hold on power illustrates a basic fact of life in the Philippines: the building block of politics is not the party, it is the family. Elections are games of musical chairs where clan members follow an intricate choreographed dance that sees them trade positions, or hand them down to kin. But when members make a grab for the same chair, elbowing each other aside, the dance is thrown into disarray. Two feuds now riveting voters involve famous families, that of Estrada (convicted of plunder then pardoned before he served a single day of the sentence) and former vice-president Jejomar Binay, currently on trial for corruption.

The Binays built their dynasty, and wealth, running the city of Makati, the nation’s financial heart. Jejomar, now 75, started out as mayor in 1986, became vice-president in 2010 and unsuccessfully ran for president in 2016. One child, Nancy, is a senator. Two other children are fighting for the mayorship of the city: Abigail “Abby” Binay-Campos, 42, and Jejomar Jr “Junjun”, 41. Junjun became mayor in 2010, and was serving a second term when he was dismissed from office for corruption in 2015. His sister Abby, who had taken a turn in Congress, decided to run for mayor and handily won in 2016.

In 2015, the court of appeals reversed the decision to disqualify Junjun from public office.

He announced he would run in 2019 and reclaim the mayorship – only to run into the opposition of sister Abby, who announced she would also run next year. In a television interview, Abby implied there had been an “agreement” between the siblings that she would stay more than one term. She said the siblings had long had differences, which were only being brought into the open because of politics. Abby said she sought re-election to oversee projects she had started. “I’m afraid if someone else wins, they might trash all my projects.”

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According to Jean Franco, a political science professor at the University of the Philippines who once worked at the Senate, the Binay feud has a gender dimension. “The family probably think Abby was just supposed to be a benchwarmer, keeping the seat warm until male politicians could again resume the position.” She said squabbles such as those of the Binays “tell us [these dynasties] are really out to monopolise power”.

In a 2013 speech, the late senator Miriam Santiago claimed the Philippines had 178 active political families, making it the “world capital” of political dynasties. Ruling families go back to precolonial times hundreds of years ago: before the Spaniards colonised the islands that eventually became the Philippines, the archipelago was a patchwork of tiny communities and kingdoms, each ruled by chieftains and nobles. The conquistadors froze this power structure in place by turning the chieftains into a local elite, the principalia, concerned only with their clans. When the Americans came along, the idea of Western “democracy” they brought merely papered over this culture.

Some dynasties have been in power for decades, others are just starting out. Almost the very first thing a Filipino does once being elected is to bring his or her family in. Next year, three of President Rodrigo Duterte’s children will be running for office: daughter Sara will campaign to be re-elected mayor of Davao City, her younger brother Sebastian will run for vice-mayor, and her older brother for Congress.

Boxing champion Manny Pacquiao, who parlayed his popularity into positions in Congress and the Senate, is now seeing his name sprouting like a shrub, with three family members running: one brother for congress, another brother and a sister-in-law for vice-mayor. Even his trainer is running for vice-mayor.

The Pacquiao and Duterte families will join a long list of entrenched clans. Out of 24 senators, 13 have relatives in public office. Even the family of the late murderous dictator Ferdinand Marcos, who was chased out in 1986, have managed to re-establish themselves. Marcos’ notorious wife, Imelda, is a congresswoman and will run for Ilocos Norte governor next year.

His son Ferdinand Jr “Bongbong” was a senator and ran unsuccessfully for vice-president in 2016. His daughter Imee, formerly a governor, is running for the senate. Imee’s son Matthew is running for vice-governor.

Dynasties almost always win elections. Political science professor Franco said “political dynasties make entry to politics very narrow” for new contenders. According to a 2016 Philippine Daily Inquirer editorial, at least 542 candidates running in elections for that year did so uncontested. The late Senator Santiago called political dynasties “stationary bandits, gluttons for power and privilege, the equivalent of Mafia crime families, and monopolies and combinations in restraint of opportunities for others”.

A dynasty can spread both horizontally – across many positions – and vertically, handing offices to members over time. The key to its power is its name, in effect a brand recognisable to voters. In the case of the Estradas, ironically it’s a made-up screen moniker: Erap’s real family name is “Ejercito” but his parents frowned upon him being a movie star so he had to bill himself as “Joseph Estrada”. He shot to fame as an action star, cashing in on the name when he went into politics.

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For the next election, both half-brothers intend to use the name, possibly confusing voters. The sight delights Filipinos who lap up cheap telenovela plots, in this instance, the patriarch of an influential family forced to choose among his children. Estrada has a lot of them – at least 10 – by several women. Years ago he declared “there is no such thing as an illegitimate child”. This might be true, but there are favourite ones. When Jinggoy went to the Commission on Elections this week to file his candidacy he was accompanied by Erap and his mother. Ejercito filed a bit earlier. Defiantly, he registered his family name as “Ejercito Estrada” and his alias (an alternative name for the campaign) as “JV Estrada”.

How the Binay and the Estrada families deal with the squabbling siblings, and whether the feuds will rupture the dynasties, is anybody’s guess. It’s unlikely the feuds will weaken the clans’ hold on power. This is the misfortune of the country: one study shows that political dynasties are associated with poverty and corruption in the regions they dominate. When different dynasties contest power, the clans are also a source of bloody violence. The massacre of 58 people in Maguindanao province in 2009 was the offshoot of a confrontation between two dynasties.

Since 1987 the constitution has a clause banning political dynasties, but no Congress has ever drafted a law to implement it. As the Inquirer put it, “the heirs of such privilege would be the last to draw a sword against their class”.