I need advice Tw: talk of legal drug use but illegal use of the person using isn’t of age still a minor

Sorry if this is long but anyways

My hubby and I are living with his grandparents while I’m pregnant my hubby and his grandparents smoke weed I do to but not while I’m pregnant anyways the past two month his little brother has been stealing our stuff iv seen him take our torch I v seen him actually smoking it and he’s olny 14 we are both over 21 anyways way earlier this morning I got up used the rest room and came back to bed and faced the wall to avoid hallway bright lights anyways as I was trying to go back to sleep I heard him open his door come in steal our straw and leave and grabbed his grandpas torch that sits Infront of the furnace he grabs that goes to his room I try and wake his brother up and tell him I kinda got him up and told him his brother took the straw he didn’t do anything I looked around just in case he dropped it by accident but nothing gone then couple minutes later he comes back and tries to hid it in his cloths but he dropped it. Grabbed it and put it in the place he didn’t find it he lefted got dressed when to school I got up and it was still hot I got up felt the torch his grandpa hadn’t used in 3 hours sue enough still freaking hot and just yesterday my husband saw him steal his dab pen and told me he gonna drug test him but still hasn’t he said the same thing when we first caught him with our stuff how do I bring this up to my husband again or should I just go to his grandparents i know he’s gonna say let me handle it no not anymore it’s been 2 months and he hasn’t done anything to attend to step up or tell his grandparents or drug test him like he said he was going to he gets in trouble at school we caught him and his girlfriend and his friend smoking at the mall also I might add his little brothers friends brother stabbed another 14 yr old when they used to be friends and now I’m worried that those are the friends that are getting him to smoke get him in trouble he’s been accused stealing guns from people throwing bricks at cars house windows threatening to k*ll/shot/stab all the people he has beef with with how his friends brother stabbed and old friend makes worried even more his friends are gonna turn around and stabbed him or he’s gonnna turn around and stab them if they ever have beef so I need help on how to handle this or if I even should intervene at the point