I have to say this again, the selfishness we brew these days in our Igbo families, I really don't get it. I am sure the problems between your father and the brothers arose because either your father or mother is trying to be Lord over them just because they live in your house and they resisted.

Your parents should learn to tolerate his brothers. As you said, they can't go and live in the bush, the so called ancestral land till they build theirs and you also know they are not capable to.

Imagine, what your father and his siblings are going through and you think later it will not be the same between you and your siblings. Let me tell you what will happen, if you guys succeed in pushing your uncles out. The next fight will start between you and your siblings over same house. I am telling you from experience, it is psychological. I has happened in many families I know, even mine.

Moreover, which relationship do you want to maintain with your cousins when through your parents you chased them away from the house.

This is the same problem that happened in my paternal family and now happening between my maternal uncles. People will never learn. The level of selfishness these days is really overwhelming. I don't get it.

My story;
If you like learn from it.

My uncle built an up-stair (big house) in the early 80's. Both families all live in the city, so we just come back to stay in the village house during Xmas and sometimes Easter. Within the few days in the village, their mum and mum will always quarrel. I mean sometimes even physical because both women were always at loggerheads with flimsy things. E.g one of my brothers (a kid then) 'pooed or peed' in the compound, my mum was cooking here and not there. So this quarrel has been there for years when we were kids till our late teenage years when it escalated. My Dad even though not buoyant, started to build a house but then they were not even patient enough for my Dad to near completion of the house before we were sent packing. My Dad had to sell a small property in the city to even roof the building. Then we moved. Of course the relationship dwindled, everybody started minding his or her business.

Now, in less than 7 years, we are better of. Completed my Dad's building, built another with complete finishing and live better and bigger. However their house remained uncompleted as it has been, no fence, not tiled, no paint and all that. Now, they all want a closer relationship but naturally it can't happen, the discord is there already. The news around the village now is that my cousins (now adults and married) are quarreling on who will occupy upstair of the house and who will stay down. Imagine.

Don't neglect people. Nobody is God. Everybody fit pick.