I know some children that like to have weight on their body when they sleep. It has been know that using a weighted blanket helps children with autism. These blankets are not just for those with a condition. I, myself love to have the weight on many blankets just because it feels so good! Here is a post I found for how to make one with out the ridiculous price they try to charge for a “specialty” blanket!
Let me know how it goes for you!