Our oldest one (now 30) had a terrible time about age two and wouldn't sleep at all, until he'd collapse from sheer exhaustion. My ex-mother-in-law solved the problem with an old Mississippi country remedey. Probably not very PC these days, but it sure worked. Fix a four ounce bottle with one ounce of whiskey, three tablespoons of sugar, and the rest water as warm as the little one will take it. He never got even half-way through before he zonked out. The worst of it was that all his sphincters seemed to relax at the same time, so we had to stand by with a fresh diaper close at hand. That was usually good for 6-8 hours of blessed sleep, and he would awaken as a delightful and happy wee person. My recollection is that we didn't need to resort to that "cure" very often before the problem was either cured or just went away. Our second one, born 12 weeks premie, never had the problem. They're all unique individuals.