I'm guessing that you might not have A/C there in Germany, I think I'd die without it. Well in honesty with the 110 degree weather here in the desert it's actually possible.

But here's my reccomendation, make an ice pack for her. Take a ziplock bag (it's a plactic bag that's closeable) Put in a wet rag then freeze it. Then once it's frozen you can cover it with a towel or cloth and put it on her bed. Since they should be cheap to make you can keep several in your freezer then just change them as you need to.