My Family Was Back in Las Vegas for Christmas. The World Was Ours.

It was almost the night before Christmas, and the house was winning.

Its creatures were stirring in the secondhand smoke.

A man in a knit Santa hat belly-laughed outside the Bellagio, a cigarette in one hand and a Modelo tallboy in the other. Guests race-walked toward the card tables in reindeer socks and plastic antlers. Small dogs in seasonal sweaters rumbled by in baby strollers.

And my septuagenarian mother stepped toward an inscrutable dragon-themed slot machine — down $60 already but determined to turn it all around.

She mashed a button. Lights twinkled. The contraption purred.

“Yeahhhhhh!” she said as the winnings poured in, narrowly outpacing her initial loss.

“Break-even!” my father shouted.

“I didn’t know you could win money on these!” my wife, Alexis — a newcomer to this family tradition — said from behind them.

We were back in Las Vegas for Christmas, and we were up $1.25. The world was ours.

Every family has its holiday rituals, the choices and tics that can seem inexplicable to even the most open-minded friends. And for some 20 years now, since I was a teenager, my family’s holiday has generally looked like this: a reel of (relative) sin in a Vegas casino, lit in its come-on-down color wheel, scored with the clack of blackjack chips and the Paul McCartney Christmas song (“Simp-ly haaaa-aaving…”) that seems to play above each table as a matter of Nevada state law.

There are, of course, a thousand Vegases tucked within the city limits: nocturnal or outdoorsy, tipsy or kid-friendly, gaming-averse or financially ruinous — well beyond our annual habit of losing a couple hundred dollars (and maybe a couple hundred more) when our cards or N.B.A. picks break bad.

Ours is a Vegas in bed by midnight, mostly sober, anthropologically fascinated with day clubbers and perpetually dismayed at the volume of restaurant music. “I’m going to spin after this guy’s done,” my father said one night, threatening to replace the D.J. at Best Friend, Roy Choi’s fantastic-but-deafening Korean fusion spot at the Park MGM.

For better or worse, I have spent far more time in Las Vegas than in any other vacation destination, absorbing over the years a procession of fateful (or at least memorable) snapshots. There was the time when Jay Leno, apparently surprised to see a pubescent-looking high schooler at his show, called me out (correctly) for inspecting the cosmetic enhancements of the middle-aged woman to my right. There were the regular…