Hahnemann taught to check for exciting causes before making a homeopathic prescription. As a therapist, I strongly endorse this attitude; I would apply the same advice to psychotherapy—why spend years in treatment if the problem can be solved by removing an environmental pathogen? For a (mostly civil) discussion of the issues involved, see Valerian’s thread, “Baby Girls Tantrum.”

Although childhood development leaves a great deal of latitude as to when different milestones are achieved, by 3 ½ years old your child really should be sleeping through the night. Parenting strategies might help you reach your goals, and in some situations family counseling might be recommended; participants in this BB have given good parenting advice in similar situations (again, see the thread on Baby Girls Tantrum). Dr. Leela’s advice, above, is also to the point. If these approaches work, this is fine, but I am concerned by your descriptors: your child is having “great” problems with sleep, and you say, “Please help!” If these in fact point to a somewhat more serious or persistent problem, then parenting strategies may not be enough. Are there other behavioral issues you’re concerned about? If so, I’d be happy to review them for possible clues if you care to post them here.

In brief, I wouldn’t want to ‘solve’ the problem, any more through homeopathic prescribing than through use of a sleeping pill, if that meant leaving ‘exciting causes’ untouched. Many environmental sources could lay at the root of this problem: dietary sensitivities, chemical sensitivities (see Baby Girls Tantrums for a case example of a teenager with nightmares), or even Electromagnetic Fields from television sets or other electronics. I would also be happy to review these with you if you are interested; I also refer you to Doris Rapp, “Is This Your Child: A Guide to Hidden Allergies in Children and Adults” for a broad and detailed survey of the field.

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"The need to perform adjustments for covariates...weakens the findings." BMJ Clinical Evidence: Mental Health, (No. 11), p. 95.... It's that simple, guys: bad numbers make bad science.