“It is a superstitious business—childish, really—the marking, or even the noticing, of anniversaries like these. Such fastening pretends that one day can be like another, pretends that every day is not, ultimately, only its own day, the only version of itself that will ever come. But ‘Daddy’ is itself a poem built on a bedrock of anniversaries.” At The Paris Review Daily, Belinda McKeon marks the birthday of an oft-revered poem.