Elderly Monitoring System What's The Best Monitor System For An Elderly Person?

What's the best monitor system for an elderly person? - elderly monitoring system

My stepmother, brother, who is 87, lives with us. Sometimes our obligations require us to work for several hours. I wonder what he used, it would be a life-line emergency - something like "Hanging" could. Is there anything better? Some may recognize a problem - for example, a case, etc. - take no action?
It has 99% of their marbles ... but just in case!