I purchased a mat 14 years ago that goes under the baby and detects movement as subtle as their breathing. I searched Babies R Us and found them under the categ

I purchased a mat 14 years ago that goes under the baby and detects movement as subtle as their breathing. I searched Babies R Us and found them under the category "Movement Monitors". It was a little un-nerving the first few times it went off as a false alarm when he would roll off the sensitive area, but it otherwise gave me a lot of peace knowing it was there.