It dawned on me this week that, at 20 months, my son F is exactly the same age that his brother S was in November 2000 when I got bit by the children’s writing bug.

I remember S’s age so precisely because what got me started in this craft was his demand that I tell a particular story over and over — the Legend of How Daddy Installed a Smoke Alarm, it was — as well as his own enthusiastic retelling in his toddler verbal shorthand. There were more drill noises in his version.

And I remember the month so exactly because the life-changing call for me to begin writing for children was an immediate thing. It was easy to pin down chronologically. I was in my closet getting dressed for work at the particular moment that the notion hit me, and I composed my first story as soon as my duff hit the seat of my office chair later that morning.

That first story began, “To make their house safer, one day S’s daddy decided to install a new smoke alarm — and S got to watch and help.”

OK, so it was weak. But S liked it, and I made it better. I appropriated his drill noises.

And now I’m wondering what inspirations lie in wait now that F has gotten to that age and begun making drill noises of his own. He’s our last one, so I’d better be paying attention.