My 83 year old mother with Alzheimer's moved in with my family and I about two months ago. She was living with part-time caregivers and at night she was starting to go outside. We couldn't afford overnight caregivers, so she moved in with us. We remain concerned about her wandering. We had a double key lock installed on the front door. One of us is there almost all of the time, but once in a while we need an outside caregiver to fill in for us for a few hours. When the outside caregiver visits, mother tries to go out the front door and is getting frustrated with the double key lock. Any suggestions?