"Look at me! I'm doing great. Aren't I doing great?"

"Yeah, you really are, Mom. Look at you. You're doing great."

"I am!"

My mother has had this conversation with a lot of people today. It's her 85th birthday, so we're indulging her more than usual. She's suffered through much in the past decade: breast cancer, followed by a disease that left her paralyzed for a year, followed by neuropathy.

No one is talking about that. We probably should be making more of this birthday. Could we have done more? She and my father seem thrilled.

The party is winding down. My daughter, Anna, is playing her oom-pah-pah song on the piano, looking over her shoulder as my nephew's 2-year-old daughter, Emily, dances, all blue eyes and smiles. The same song, the same dance, over and over. Only in families does a show like this not lose its appeal.

"I'm missing something, aren't I?" my mother calls. She ended up sitting in a chair in the family room, and she can't see the action.

"Yeah, come on in here!" my brother calls. "Your granddaughter and your great-granddaughter are putting on a show."

"Oh, I can't get out of this chair," she says. "I'm not doing great."

The remark sends off no alarms. This is how it seems to go. My mother is great for a few hours; then she deflates like a balloon. No endurance. "It's OK," she calls. "I might just shut my eyes a moment."

No way. I stomp in and hold out my arms to hoist her up. "I'm not doing great," she says. I tell her she can be not-great in the other room as well as she can be not-great here.

I steer our mom into the living room, sit her on the piano bench next to Anna, facing out. "Dance? Dance?" Emily says, her signal to Anna to replay oom-pah-pah, and several of us shout, "One more time!" And so it goes again, with my mother's smile now part of the show. Behind her is a photo of her mother and father, taken perhaps in the 1930s. You can't help but marvel at the passage of time, all these generations. I watch Emily's twirls and picture Anna doing that a few short years ago, my nieces and nephews doing it a few decades before that, my own vague memories of being the dancer before a cheering gathering of grown-ups. I suppose my mother was once the dancer. I suppose her parents sat and watched and shouted, "One more time!" Every child should get a chance to be the dancer, a thing of marvel and joy, the center of the universe. My mother is tapping her good foot to the beat, her fingers bouncing on the handles of her walker. Claire motions to see if I notice. I smile and motion to others. It's not much of a dance, but it is right. Every old woman should get a chance to be the dancer, I think. Every old woman deserves this.

"Okay, I'm not sure I can listen to this song again," my mother finally says. "Anna, you got any others?"

Jeanne Marie Laskas writes for The Washington Post.