father in law threatens to commit suicide how to safeguard family

Hi, My father in law is an alcoholic and has been staying with my mother in law and his elder brother at my wife's residence. The house is in the name of my wife. My father in law has been borrowing money from everyone in the society and who so ever he can access without the knowledge of anyone else in the family. Recently all this has come to light and we have no clue as to how we can safeguard our family from all of this. When confronted he threatens of committing suicide. Can anyone pls help with what legal action can be taken. And also as a son in law do I legally have any obligation to my father in law. Would be highly grateful if someone can guide us through these tough times.