The boys are now going through a zealous costume phase, and Meredith and I have spent the bulk of our vacation chasing after Batman and Spider-Man and assorted creatures from outer space. Yesterday, the kids went bodysurfing in their costumes — Timmy was Superman, Tad was a bunny — and more than a few bewildered stares came their way as they emerged from the Atlantic like the survivors of some comic-book shipwreck. They dine at Nobu in their costumes, go down water slides in their costumes, climb rock walls in their costumes, stroll through the casino in their costumes, and high-five puzzled lifeguards in their costumes. The boys are no longer content with store-bought outfits; Meredith devoted the first day of our vacation to manufacturing a pair of unicorn horns, using rolled-up socks, coffee filters, and plenty of ingenuity. Though it's embarrassing to admit, I've sometimes joined the boys in their costumed reveries, patrolling the Bahamian shoreline in my homemade Hulk getup.

What fascinates me, in part, about this costume obsession is the uncompromising earnestness with which Timmy and Tad engage in the fantasies of make-believe. For them, make-believe is the real world, and the real world is make-believe. In one way or another, and to one degree or another, this is how I've led a great deal of my own life for the past sixty-some years. I've dressed up in an Armani suit and pretended I belonged among the rich and famous; I've dressed up in white linens for a cameo role in a movie called "The Notebook," pretending I was at ease in the presence of Ryan Gosling and Rachel McAdams; I've dressed up in a helmet and rucksack and pretended I was a competent soldier; I've dressed up in a magician's top hat and pretended I was making miracles happen; I've dressed up in blue jeans and a baseball cap and pretended I was a happy guy.

From "Dad's Maybe Book," by Tim O'Brien. Copyright ©2019. Available from Houghton Mifflin Harcourt.