First Reader Sends Me Back to the Drawing Board

All right, not on the whole first 50 pages. Just on Chapter Four-the protagonist's childhood. According to first reader, (also known as my husband), I changed my tone in that chapter and began writing in the style I usually use in literary short stories. All the tension drained away. At least, it returned in Chapter Five and Six, thank, God.
I admit Chapter 4 was almost a cut and paste job so I'm not surprised. And, on the bus today, I suddenly saw what has to happen in her childhood. The tone reasserted itself when I thought of the story I should tell about this period.
I am still unsure how much childhood is good for the story. Very little, I expect unless it is as dark as her adult years.
My husband, a great fan of Sara Gran's, waved Come Closer in front of me this morning. I read half of it on the bus. She does manage to sustain tension, doesn't she? I'm not much a fan of horror (although I loved Dope), but as a roadmap to what I want the book to be like, it's right up there with Megan's Queenpin, Duayne Swierczinksi, or Anne Frasier's novels.