Has she TOLD you that she is scared? Some kids just have trouble sleeping. My niece was having some spiritual problems but when they moved out of the house (rather abruptly as my sister and brother in law started realizing that the fears were actually REAL and DANGEROUS) she started sleeping fine. But now in their new home, her little sister started having trouble sleeping. My sister found that she had an allergy to milk and she was drinking milk every evening. She switched to rice or soy and it helped.
Some children need something to help them sleep, like melatonin. Many children on the autism spectrum can't sleep without melatonin. They will stay up all night!
Does she seem to have sensory problems? Does she crave stimulation (runs into things, can swing or spin for long periods of time) or avoid it? Children with sensory issues often have trouble sleeping.
You could try playing soothing music and praying with her. You could try visualization. I do this with my children when they can't seem to sleep. We pray first that God gives them good dreams and keeps all things bad away from them. I have them close their eyes and breathe deeply. Then I tell them a story (you can alter it as you like.) Have her close her eyes and breath deeply and calmly as you tell the story, but make sure you tell it slowly and softly, matching the rhythm of her breathing. She may not talk or move around. It might take a few nights of doing it for her to get used to lying still and quiet.
"You are floating on a cloud. The cloud is soft, and your head sinks into it like the softest pillow. You breathe in and out. In and out. The cloud drifts slowly through the sky and you are getting sleepy.
Now you are walking on the beach. You feel the sun, warm on your skin. Your feet sink into the sand and the waves wash over them. You breathe in an out. In and out. A little crab scurries by you. Sea gulls fly overhead, singing and looking for food. You breathe in and out. In and out.
Now you are walking in a meadow. The leaves on the tall trees are green and shady. There are flowers everywhere in yellow, blue, purple and pink. Two bunnies chase each other through the flowers as a squirrel runs up a tree. You breathe in and out. In and out. A mama deer and a baby deer munch on the flowers and grass as it is sweet and good. You lay down in the soft green grass and close your eyes. You breathe in and out. In and out. You are getting very sleepy as you listen to the wind rustle the leaves in the trees and you go to sleep, breathing in and out. In and out."
:) I hope all this helps!!
S., mom to 5!