She's giving him CBD oil

My friend has a son who is autistic. She does not use any supports offered. He does not attend any type of therapy and hasn't seen a doctor in at least two years. His autism is very severe, he is 8 and not potty trained, can't speak a single word, and he is extremely violent. He kicks, bites, punches and chokes his parents and other children. He does attend school, but that's it. Any supports the school has suggested get ignored.

She recently told me she medicates him with CBD oil containing THC. She said she gives him it twice a day. Not sure how much. She is not prescribed this. It is NOT medical CBD oil, she gets it from her drug dealer (who also sells her pot regularly). She says it makes him "calm enough to deal with".

I'm not sure what to think. What if the oil she receives is laced? It has THC in it. That can't be good. I'm all for CBD and it's benefits, but only when from a safe source. The guy she buys it from sells other way harder drugs. Idk I'm concerned. Would you guys do anything? I've talked to her but she just shuts me down.