Decades ago every event or holiday was an opportunity to dress my young children in colorful costumes. Our calendar was always full. Parties and picnics. School celebrations. Parades. Pleased with their new outfits, and anticipating the festivities, my kids posed, sometimes smiling, for the camera.

“I can’t wait for them to start school,” I often said back then. “It will be so good when this day is over.” Motherhood was exhilarating but exhausting. I was always wishing time away.

Yesterday a friend dragged me out to a park to see the fireworks. I couldn’t remember when I’d last walked in the park, and was amazed at the hundreds of young families in small clusters in every direction. We sat on the base of a lamppost by a family camped out on a blanket. The little girls swatted each other and blew bubbles. Giggling, in polka dot dresses, they swirled around with glow sticks. I watched them as much as I watched the show in the sky.

“Growing like weeds,” people say about children. Yes, they grow up and away. Too quickly, it seems, looking back. And suddenly you find yourself mesmerized by the sight of other people’s laughing children, like they’re rare creatures from an old dream.

What moment in time slipped away too quickly for you? If you could spend an evening back in your past, what and where would it be?