Brother behavior issue

We are two brothers,wife and 2 -2 children of both with Mother and Father, earlier we were living in joint family ,where house purchased by Father ,in name of elder brother and himself.Later on due to large distance from my office i with my family decided to shift near to office (earlier it was 52kms away ,now 20 kms),but brother started creating nuisance and become violent in several occasions,any how we shifted,after span of 6 months ,he started creating problem to parents and finally told them to move out and to shift my they are staying with me but willing to go back to their house.but brother clearly told if they will come he will vacant the home at the same time if he will kill himself with family ,we all will be responsible.He also told that he will write property to any one ,to whom we will suggest. one thing to mention that he left job almost 3 years back and doing business,we don't know how business is performing and 1 year back his wife gave birth to male child but having little clift ( above tongue) related problem,as suggested by doctor ,it is very minor problem, we are not able to understand ,why he is doing these one having any interest with property,but we are worried either he may hurt himself,family or any one of us.he is not open to meet psychiatric also.Father is in old age and not able to understand what to do. Please suggest