We purchased it when our first daughter, Emily-Grace, was about 4 months old. This may sound like an exaggeration (it's not), but the third night after I started using Dr. Weissbluth's sleep recommendations, Emily-Grace slept through the night! At first I thought it was just a coincidence, but after a week of having her sleeping through the night, I was convinced that it must have been the new sleep routines that made the difference. She did start night waking again when she was about 6 months old, but my lactation consultant suggested that perhaps that was an indication that she was ready for cereal (she had been exclusively breastfed to that point). The night waking continued until she was about 9 months old, so I don't know whether the lactation consultant was right or not, but at least we knew how to deal with the night waking, thanks to our trusty "sleep bible."
When Emily-Grace graduated to a "big girl bed," Dr. Weissbluth's book not only gave us effective strategies dealing with our daughter's repeated getting out of bed, but also gave us the reassurance and peace of mind that, even though it may not seem to work at first, it would if we were persistent and consistent - and within a relatively short time, it did work! We used Dr. Weissbluth's sleep training strategies with our second daughter, and she is also a very good sleeper (actually, she is a better sleeper than her older sister, partially because she has an easier temperament, but also, I believe, because we started sleep training her right from birth, rather than when she was already a few months old).
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