The facts of this case seem to support a call to child protective services or 180096ABUSE. If the mother is using, the man is using ( what was he convicted for) and is sleeping in the bed with your child, it sounds like an imminent risk. Otherwise, you can file an emergency motion for temporary sole timesharing; for supervised contact; and yes, her family or other eye witnesses may testify at the hearing. You need a lawyer.
If by "full custody," you mean that the mother will be completely unable to see her child, I doubt it. However, if you can prove these allegations, especially with testimony from the mother's own family, I think you have an extremely strong case for supervised timeshare.
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