I knew that Marcus could tell you Dylan’s exact birthday, and which subjects the boy struggled with, and the precise severity of his peanut allergy.

And I knew that Marcus could not have told you, without checking the calendar on his phone, what grade his own son was in.

He had a father’s attentiveness, finely tuned and reliable and warm — he had simply aimed all of it at another house.

That was the part that took me longest to understand, and hurt the most once I did.

It was not that Marcus was incapable of showing up.