They need a:
Satin pillowcase!
I was blown away by how soft these are; you always hear about silk pillowcases but oh my goodness these satin ones are INCREDIBLY SOFT! I bought two of these in the blush colour for my nieces, but there are some pretty cool prints and colours available as well. I’m told they are great for your skin and hair, and that they also keep you nice and cool at night. 😎