Lawful Precautions For A Threatening

I made a house in my ancestral home in the year of 2004 when my father was alive. Though I have been living away for my job. In my house there live my nephew. I occasionally go to see my widow mother but my nephew doesn't like me going there and he uses very low heinous language towards me even try to assault me physically. Recently he is threatening me of committing suicide involving us.What lawful precautions should I take in such a situation ?