Children with sensory processing disorder can have trouble sleeping which is a very tiresome situation for the parents and the child.
Here are some ideas you can try that can help ( I tried some of them, sometimes they work and sometimes they don't, but it's worth a try)
1- deep joint compression before they go to bed (https://youtu.be/oh4YHC4-BQQ)

2- don't give dairy products before bed time
3- no iPads or phones or any screen time two hours before bed
4- massage using magnesium oil especially the souls of the feet then cover with socks) I will try this as soon as I get the magnesium oil and give you all feedback. I found the magnesium oil sold online on a page called black lotus
5- give your child a stress ball
6- using the big gym ball, let your child sit on it and press on their shoulders down so try bounce on the ball.
Then have them sleep on their tummy on the ball and roll the ball front and back..
https://youtu.be/4i258YX-6Do
I found this video very useful
I'm going to try these techniques the coming month and let you all know how did it go
If you're not sure what to do please as our doctor or therapist. I'm just giving you ideas to ask your doctor about as sometimes they will not offer you these solutions unless you ask about them.

Have a great day and hopefully a good night sleep 😴