Difficult to get out of bed

I have a double problem, but it’s similar to yours. My brother is big, so I had to use 2 mattresses to make him feel comfortable, but it turned out that he’s in pain just like you are on them. He’s not complaining, but I can see that he’s not feeling well. Should we try mattresses for big people? Will ordinary mattresses like these fit, or do you need extra functions in them?