Deceased mom took loan from relative who is now harassing threatening

One of our relative is constantly sending text messages and phone calls which are so abusing ,threatening and harassing .actually the problem is that my mother who is dead now took some money(25 Lakhs they say )years ago from her sister we don't actually know what is that amount taken , later on when she passed away these people (my mothers' sister and family) came to our home saying that we gave some amount to your mother and wrote some bond papers and with interest of (5 rupees which is too much for us to repay) now they are saying the amount in crores .and to even pay them our land disputes are going in high court and they should be cleared and we should sale it and then pay them back but it is taking time for us but they are constantly provoking us by abusing and threatening that:- 1.I will kill you very soon 2.I will not let ur son become a doctor (which is aim of my son) 3.I will not let ur daughter getting married. 4.I will make ur family leave this place.