Teenage girl  (SVGiles | Getty Images )

There's one comment every new mother gets, usually from someone you could never imagine being yourself: an empty-nester—or, worse, some mom of a teen, touching your shoulder as her daughter stands next to her, visibly annoyed.

"It goes so quickly. Just you wait."

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I've abhorred those words since the moment my little girl was born. Every time, it's like a cast spell, and I ward it off by thinking, No. We will go slowly. We will not be like you.

But here I am, at exactly the place I thought I'd never be, and my daughter is only 11. I have years to go before she leaves the nest. But it's like she woke up the other day and was… different. Defensive, cranky. Like her love for me drained out in her sleep. I am sad and I am scared. I've even started having nightmares—ones where she's in danger and I can't get to her. They wake me at 3 in the morning, and I creep to her room and find her, in her new PBteen bed, sleeping in her braids, the blue light from her clock radio showing me that she is still alive, yes, and so suddenly big.

When she was a baby, I'd get up in the night and put my finger under her tiny nose to feel the warm ebb and flow. Sometimes I'd kiss her forehead, or her unobjecting lips. I did it just last night, and for once, no irritated preteen hand swiped my kiss away.

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The morning comes, and she's at my bedside at 7 a.m., grumpy that it's another cruel day, one in which she will be forced to suffer the drudgery of family life. Getting out the door will be brutal for her; just the act of zipping up her parka will bring her to boiling frustration. She will tell her little brother to shut up, even though all he said was, "You've got it inside out," and she'll yell at me even though all I asked was, "Do you want turkey and cheese or ham and cheese?" I know it's her job to move on beyond the universe of her family; it's the progression of life. So this is less about her and more about me. I am grieving a very particular loss: the loss of the "little" in my little girl.

You know, for a long time her childhood did go slowly. There was a delicious stretch of years that felt static and impermeable. She'd slip her hand into mine at the street corner. She'd stroke the tiny hairs between my eyebrows, not scorn their lack of grooming. She'd pull a chair up next to me at the kitchen counter and watch as I cut carrots and celery for my tomato sauce and say, "Your food is made with love" (not that pasta makes you fat, like she does now). More than anything, she liked me to sing to her—at bedtime, on walks, in the car on the way to school. She loved to sit at the piano with me and "take a ride" on my fingers as I played her a sea shanty called "The Golden Vanity." She'd suck her first two fingers as I sang that sad, long song. In fact, her slide into tweendom began with "The Golden Vanity."

"It's depressing," she announced one day when she was 10. "Please don't sing it anymore."