Ped brother/ mothers upset. Anything more I should be doing?

Yes it is a huge tragedy for all involved, so what is the question. You had no role in what has become of your brother except the unfortunate one of common parentage. It might help your mother to attend a family support group for those with ually addicted family members although those are not too common except in very large cities. I suggest that you continue to keep your distance as things unfold since none of you know which of the neighbors and friends or other family members may come out of the wood work to add fuel to this fire. Sorry.