I suppose it somewhat depends on what they allow.

The reading material is a good suggestion to help relieve any tedium.

I'd also just like to point out that people usually appreciate frequent short visits rather than rare long ones, which can tire everyone out. When someone is having such a difficult time, friendship and companionship is a very precious gift. And having something to look forward to in a day, even if just for a short while, means a lot.

Best wishes to both of you.