Ask the Mom what triggers the Rages try to work out what is happening just before,as she doesnt do this with the sitter ,As usual and I do know there are times for Meds but they do sometimes make a situation worse and they nearly all have side effects, read the paperwork that comes with the Meds,this is thier decision to come off meds and if they do they need to ask how they do it, very slowly I think,How do the other siblings react to her are they kind or is there any teasing or problem there ,should be addressed and Mom cant see it.Has she plenty to do and doing things she likes to do, how does school go is there any issue there , get her Mom and you to be observant and check out what is happening this sounds like a cry for help.