Alert system for elderly family member?

[Mama2Fussy]

My maternal grandfather is currently living in a very large home with the rest of the family, 7 people total.
He has his own room and bathroom, and basically an entire level of the house to himself.
He has multiple health issues, including severe diabetes and kidney disorders. Most of his muscles have atrophed due to lack of energy and excercise; and his blood sugar levels are highly irregular and sensitive.
Often at night when waking to use the bathroom, he falls. He never calls out for any assistance, to afraid to disrupt anyone's sleep. Instead he flails and manages to get himself up after much struggling.

I'm wondering if something exists SIMILAR to life alert that might be employed here. An alarm that he might be able to activate that just alerts a specific person in the house, so he doesn't have to call out. Or even something automatic, that reacts to sudden changes in stability.

Does anyone know if such a product exists?