Look I am not saying to lock him up and throw away the key - and to be clear we are talking about schizophrenia not down syndrome, mental retardation or autism. And I am not stigmatizing mental illness at all - I am saying that young children are not equipped with the tools to deal with some of the behavior that a schizophrenic (especially paranoid) will at times display which is why their interactions should be supervised and time limited.
If you would like I can tell you of some of the behavior I am speaking of- seeing people and hearing people that are not there , being afraid of the people they are seeing which no one else can so they will want to hide, run or get away from them. Refusing to watch tv cause they think someone is watching them and that goes for air planes and helicopters. Being afraid of the telephone as well. Not bathing themselves for long periods of time and getting upset if made to do so . All hygiene is out the window. Going to the bathroom in their pants for whatever reason sometimes just cause thats what they have decided. The list goes on and if you dont think this will scare a little child that does not understand you are wrong it scares most adults.
This is what happens when they go off their meds and if they are not living in a place where this is supervised to make sure they are on them.
What I am suggesting is that Barb limit the amount of time the children in her care are around her son. There is not any reason under the sun why she should not go see him or his sisters as much as they can - just dont let him watch Jace as he was last year alone or any of the children. Dont have him living with the children. Really cant she still see her son but afford to get a babysitter to sit with the kids some of time?
And get some professional advice about how to handle this - these children need to be somebodies first priority.