I had a dog and cat for ten years in early MS. They slept with me on the bed and I trained kitty to sleep at my waist on one side, the dog at my feet on the other side. So I was neatly pinned in position on my back because none of us moved very far all night.
Little did I know what a gift that would become, how handy it would come into play when MS restricted me to basically one sleeping position. Rolling on my side became a big fanfare where I had to inch myself over in two degree increments., which would be enough to wake myself up full on. Not worth losing sleep over. But the pets taught me one position is more than sufficient, and I continue to have restful sleeps on my back, waking up in the same position I fell asleep in. Therefore I have no need for guard rails or fear of rolling out of bed common to my demographic.
So thank you Beethoven for rolling over to make room for MS.