My Cousin Is A Torn In My Mother's Flesh. How Do I Handle It?

My fellow brethren please I need your advice because I don't know what to do to avoid people misinterpreting what my actions might be. My cousins brother is disturbing my mother so much that I feel like shooting him. Since this year alone I have bought 3 phones for my mother which he stole all of them including her money.



My mother is old and cuppled with the accident she had, she now move with clutches. This guy threatens my mother @ any slight provocation from my mother which may be caused by my mother cautioning him not to fight his own mother and beating his sisters. His father had disowned him because of his irresponsibility so the father left his wife under the mercy of the young man. He smokes weed, gamble and stealing. Just yesterday I got a call from home that he carried block to stone my mother when he was asking his own mother for money and his mother started quarreling him and both of them wanted to settle with my mother been a scapegoat.

Please I will like to discipline this boy at least because of my mother but all my plans are negative towards him. I want him to be useful to him self. Please experts in this forum suggests for me the best way to discipline him before he kills my mother oh