Unfortunately, this book is not yet translated in Japanese, otherwise I would have recommended this to many of my Japanese mother-friends. There was so much information that seemed relevant to me that I underlined many pages.
Explanations of why a child's brain needs fat for development, why nouns come first and verbs towards the end were brilliantly detailed. It has been one of the most useful books as a novice mother.
I would recommend this to those who feel wanting with generic parenting books.