A variety of pumpkins are mingled on the sale displays.

As another Halloween arrives, I’ve been thinking about an earlier All Hallow’s Eve I spent in Houston and what it taught me about the fragility of life’s gifts. It’s a lesson that’s returned to my thoughts this autumn, as Americans enter the final leg of a year marked by loss.

In 2004, a national parenting magazine asked if I could take my wife and two small kids to Houston for a long weekend, sampling the city’s children's attractions for a travel story. We arrived just in time for Halloween, taking in everything on someone else’s dime. Butterflies landed on our shoulders at a three-story aviary in the Museum of Natural Science. We ice-skated at the Galleria, where I instructed our youngsters, in the interest of research, to visit a designer candy store and snag as much chocolate as they could handle. We gazed at moon rocks at the Space Center and fed stingrays at Kemah Boardwalk. It all seemed magical, perfect.

Near the end of our trip, we entered our hotel elevator and found a small, bald child in a wheelchair waiting inside. To be near the prime attractions, we’d booked a room in Houston’s medical district, which boasts some of the best hospitals in the world. It was obvious that the young girl in the elevator had come to the city to fight for her life.

Her presence shook me, providing a potent reminder that my family’s past few days of glory weren’t inevitable. Our luck could have changed in an instant.

In the years since we returned home from Houston, my memories of the city have evoked for me those two compelling realities — the enormous promise and plenitude of any given day, and the alternate sense that none of it is guaranteed.

That came clearly into focus for me yet again over the summer, when Hurricane Harvey flooded Houston and washed away so much that those of us who love the city had taken for granted. Houston’s suffering has seemed, in retrospect, a kind of keynote for the calamities touching other parts of the country these past few weeks. Florida and Puerto Rico reeled as well from powerful storms, and much of California’s wine country, a cradle of agricultural plenty, now stands in ashes from horrendous wildfires. The mass shooting in Las Vegas brought its own version of hell.

Trick-or-treating hints at that fickleness of fate, the randomness of chance that can bring joy or disappointment at each new door we approach. The whole whistling-past-the graveyard sensibility of Halloween, with its grinning skeletons and mock monsters, is a way to bravely laugh, rather than cry, at our vulnerability to what life throws at us. Collectively, on the last night of October, we resolve that even in the lengthening shadows of a dying year, wonder, rather than weariness, is the proper response to our complicated human condition.

In this October, perhaps more than others, we need what Halloween can give.

Follow Danny Heitman on Twitter, @Danny_Heitman.