AMY JUST TURNED 27, and she has her first real job in New York. Amy is going to make it in the big city, but when the city gets too big she likes to come home. Home is where her dad is. And I'm where her dad is, since I'm married to him. I am Amy's stepmother, although we rarely use that title. I entered this picture so late. Amy was already graduating from college when I showed up, and Peter, Alex's son, wasn't far behind.

When you are married to a man 15 years older than you, these are just some of the things you deal with.

You deal with forgetting, really forgetting how old you are. Aren't I the kid? How in the world did I get bumped up here into the parents' generation?

Amy calls. Her plane gets in at 9. Should she meet us at the gate or the baggage claim?

When I go home, my parents always meet me at the gate.

"The gate," I say.

"Okay, great!" she says, and when she hangs up I tell Alex we'd better hurry up and get to the store.

"The store?"

Because Amy is coming home. When I go home, my mother has my favorite foods in the refrigerator. She always makes sure to pick up Granny Smith apples and Camembert cheese. We'd better get Diet Pepsi and plenty of fresh vegetables, because Amy doesn't eat meat.

This is all new for me, being part of the home that someone runs to. I'm not sure how to be, how to act. It's not that I'm nervous or even awkward around Amy. In fact, if anything, when Alex's kids come home, I turn into one of them. I sneak cigarettes with them on the porch.

Alex hates that his kids smoke. I quit decades ago. But when Amy and Peter are around, I regress. "Is your dad watching?" I'll say, as if their dad were my friends' dad, not my husband. We'll giggle and maybe even do match tricks.

"Oh, God, you're being teenagers again," Alex will say out the window. But I think it makes him happy to see how Amy and Peter and I have become such good friends.

Usually, when Amy is around, there is also Peter and a throng of their friends around, too. It usually isn't just Amy. The situation doesn't usually remind me of my mother and me.

When we pick her up at the airport, Amy looks exhausted and she desperately needs a smoke. Alex and I get her bags while she steps outside and lights up. We take her home, and when we get in the house she starts talking. Talking and talking, sitting in the big chair, shaking her head and her fists at the world and all its complications.

I am less forthright. When I go home, I am more protective of the contents of my heart. I sit on the floor behind the coffee table and tell funny stories. Well, I think they're funny. And my mom thinks they're funny. But I do sort of go on and on, now that I think about it. I do add an awful lot of extraneous detail. The attention she pays me, it must be exhausting.

I never realized how exhausting it must be.

"I'm so tired," I tell Amy. "I'm sorry." And what does she want to do all weekend? Does she want to go shopping? Does she want to go for a hike? How should I plan our time? Should I plan our time? Does my mother plan our time?

I wonder if my mother has other stuff to do when I come home. Truth be told, I really need to get my zinnias in tomorrow; I'm so late. And I have this book deadline. If I don't knock off a chapter this weekend, I'll never have this thing done by fall.

I can't actually picture too much of what my mother does when I come home. All I know is she is there. I think I spend a lot of time off by myself listening to loud music. Is she waiting for my cue?

I wonder this because Amy spends much of the next day in her room, listening to loud music. I have all the time in the world to work on my chapter, and plant my zinnias, too. But is this the right thing to do? Is Amy bored? I am waiting for a cue.

She joins me in the garden that evening, asks if I want help.

"That's okay," I say. Because the last thing I would want to do is help my mother weed.

"Do you think I should call Chris?" she asks. Her boyfriend from high school.

"Absolutely," I say. "I think you should surround yourself with adoring men."

"Cool!" she says, and calls him. But he's away for the weekend. Bummer.

"Do you want to listen to music with me?" she asks.

"Of course," I say. In fact, I'll do whatever she wants. Because this is her time, not mine. Going home, it's my time, not my mother's. It's my life, not my mother's. This is just what it is to be a daughter. This is the invisible, wondrous gift.

This is the circle my mother started. This is my model. And so, in a way, this is my mother's gift to Amy, too.

Jeanne Marie Laskas's e-mail address is laskasmail@aol.com.