Answer: I don't have an autistic child but my son got just a few hours sleep almost every night from age 2 to age 10. After age 3 he wouldn't take naps anymore. Like you I was exhausted from sleep deprivation. I would take a nap every evening while my husband took care of the kids because I fully anticipated pulling another all-nighter. In hindsight it was pretty insane and I couldn't get help from anywhere. The lack of sleep did cause a lot of behavioral problems. He was diagnosed with ADHD. He started taking Ritalin (and later tried other stimulant medications) to help with behavior but that did nothing for his sleep problems and his behavior only improved somewhat. I saw a child psychiatrist when he was 10 who placed him on a low dose of Clonidine and stopped the stimulant medication. He's nearly 14 and still can't fall asleep at a decent hour without meds. He really tries though but the meds is the only way he can fall asleep at a reasonable hour. Sleeping well at night improved his behavior dramatically.I know your son has autism but maybe a child psychiatrist can help. Other specialists only wanted to try stimulants but his sleep problems and behavior problems persisted. Child psychiatrists also work with autistic kids. They also know a lot about medications. If you're totally against the idea of medication then I don't have any other advice. I know that sleeping well at night does improve behavior with any child who has sleep problems.