Possibly having to call DHS on my grandmother

I have a little brother that I have a 21 year age gap with. He's 15 and special needs. He has autism. He lives with my grandmother because our womb women is, pardon my French, a bitch that likes to have men cream pie in her cunt and fuck off the offspring onto other people. I have mommy issues. Moving on. Anyway, I lived with my dad most of my life. My brother was raised by my grandma and grandpa. He's a grandmas boys. Problem is they're really old. My grandma is 93, and grandpa is 96. My grandma has dementia. Them taking care of my brother has become a bigger toll especially since he's special needs. He has accidents sometimes and when I've picked him up to come to my house he smelled really bad of pee because he had an accident and no one to help him wash up because my grandparents are just too old at this point. My brother even wandered out of the house and nobody found him for over 24 hours. They can't keep up with him. They can't keep up with his needs. One day I went over there and there was poop on his bed. He had an accident and neither of my grandparents cleaned it up. Then my grandmother's dementia has caused her to make irresponsible decisions. Especially involving my brothers social security check. She was spending irresponsibility. Didn't pay the electricity bill and they were left without power for days. A lot is going on. The problem is that I know if DHS gets involved it will break my grandmother. Even when my brother visits me because she has dementia she forgets he's with me and starts freaking out and screaming when she can't find him. Losing my brother would destroy her.