Many families will recognise the relationship - the passionate younger sibling, always bursting to break in when anyone else is talking, and his more philosophical senior, who recognises that allowances must be made.
In Kosovo, however, where ethnic Albanians such as the Gecaj family are struggling to break free of Serbian domination, such differences are a matter of life and death.
The bearded, loud-voiced Gani is in Kosovo Liberation Army (KLA) uniform, his rifle across his knees. He boasts of having taken part in the group's first-ever attack on the Serbs, the shooting of a policeman in 1992.
Fadil, clean-shaven and in civilian dress, is a leading member in his district of the Democratic League of Kosovo (LDK), the main Albanian political party, which has consistently advocated a peaceful solution to the conflict in the Serb-ruled province.
The debate between them will be mirrored at the chateau of Rambouillet, near Paris, where the international community has summoned the Serbs and the Albanians today to reach a settlement.
Fadil supports the LDK line, which is to act as though the Serbs have already given up their rule in Kosovo. The party held a referendum in 1991 that overwhelmingly called for independence and conducted elections, using private homes as polling stations, in which Kosovo's 90 per cent Albanian majority chose Ibrahim Rugova, the LDK leader, as their "president".
But the Serbs did not go away and the KLA emerged from the shadows in 1997 to take a more direct and bloody route to independence. Its attacks provoked a massive Serbian response last year that devastated the province, killing more than 2,000 people and driving hundreds of thousands more from their homes. But they also did more to persuade the rest of the world to intervene than all the LDK's years of patient attempts at negotiation.
"There are two ways to solve this problem," says Fadil. "The KLA chose a short cut, while the LDK took a step-by-step approach which avoids fighting."
"We tried that way for years," Gani cuts in, "but we got nowhere."
"We have the same aim," says his brother, ever the peacemaker. "It is true that the KLA made things go faster."
Both are bleary-eyed - they admit that they were up until 3am, arguing over exactly the same ground.
To reach the Gecaj brothers, you swing off Kosovo's main east-west highway into the Drenica district, the province's poorest and the worst-damaged in last year's Serbian offensive. Passing the town of Srbica ("Little Serbia"), known to the Albanians as Skenderaj, you reach Lausa, or rather the ruins of the village.
Here the Gecaj clan has its compound, which is as devastated as the rest. We meet in a low, newly constructed house, where the freshly plastered walls are still damp. Fadil and Gani have five other brothers - Halil, 43, who is in Albania; Haxhi, 34, who is in the room but says little, taking what is clearly a familiar role of listening to the others; Nebi, 26, who sends money from Germany; and Nehat and Esat, 24 and 22, who have also joined the KLA.
"This family is famous," says the local school head. "They have always fought for the freedom of Albanians."
So oppressive was Serbian rule that Fadil spent 18 months in prison a few years ago for referring to Srbica as Skenderaj in the hearing of a policeman.
"They beat him until his head looked like this thing here," says Gani, indicating the battered wood-burning stove, "and he still chooses peace? That's when I thought that I'd rather go and fight."
There is little room for moderates in this conflict, and even Fadil has a pistol strapped to his hip. "People didn't want to fight in places like Prekaz [scene of the first massacre of civilians in Kosovo, late last year] but the war was imposed on them," he says. "That's the only reason I have this."
Gani cannot resist another jibe: "When the shells were falling on Lausa, they didn't distinguish between the LDK and the KLA." But he adds, more seriously: "War was imposed on me too. I could live better than this: we have a family import-export business as well as the farming. I could take my wife and children to Germany: we have residence rights there. But I have chosen to stay and fight."
Both brothers know what they want from the Rambouillet talks - independence for Kosovo - but this is not on offer, neither from the Serbian government of Slobodan Milosevic nor from the six-nation "contact group" which has organised the talks.
Fadil, needless to say, is more optimistic. "We are going to show that Albanians know how to be united," he says. "We have a state structure already in place, and now we have international support for it."
"That's just your opinion," retorts Gani. "The KLA doesn't recognise your structure. That is not the reality."
"It doesn't matter that we are brothers," Fadil sums up. "We see this differently."
Haxhi at last speaks up, saying: "The biggest problem we have are these two. They are always arguing."
But for all their long-contested differences, fraternal solidarity counts most, not only for the Gecaj brothers but for all of Kosovo's Albanians when it comes to Serbian rule, and Fadil's final words serve as a warning of what will happen if Rambouillet is a failure.
"This time, we hope the West and the international community as a whole will find a solution leading to independence for Kosovo," he says.
"If there is no solution this way, we will all join the KLA." At last the brothers are in agreement. "I also hope for the same thing," says Gani.
"We are part of Europe, and if we must, we will fight to join it."
International monitors in Kosovo were trying yesterday to defuse a stand-off in Srbica, 18 miles west of Pristina, where Serbian police were trying to enter rebel territory to investigate a robbery at a Serbian Orthodox monastery.
About eight armoured vehicles were prepared to move to the monastery of Devic, where thieves three days ago made off with farm equipment. KLA rebels refused to let them enter.
Andreas Kern, of the Organisation for Security and Co- operation in Europe, said that a firefight broke out on Thursday when police tried to approach the monastery, home to nine Serbian nuns.Reuse content