The other morning, I was digging around for something in the back of my closet when I found a framed photograph I’d stashed there in one of my fits of manic tidying.

Last night I did what I ordinarily do around eleven o’clock. I shut down my laptop computer and put it away, then closed the book I was reading and set it on the lamp stand next to the sofa. I brought my water glass and my wine glass into the kitchen and put them in the dishwasher. While my husband went outside to smoke his last cigarette for the evening, I climbed the stairs and readied myself for bed.

My wife, Lael, and I had repeatedly been cautioned by our experienced friends to expect severe, relationship-altering sleep loss after the birth of our daughter. The truth was, though, that we looked forward to the challenge.

I'm going to confess something that might sound shocking coming from a writer who often takes as her subject the complex and sometimes dark experience of mothering young children . . .