"Gaby walk down stairs," you announced.
And as I talked you down, like a mountain-climbing instructor -- Slow, take it slow; good, hold the rail -- my mind flashed back 20 months.
It happens to me every time you reach a new milestone or master another small skill: a jolt of pride, a sigh of relief, then the wisps of doubt. Are you on or behind schedule? Is your progress normal? Will I ever stop wondering?
My mind rushes back to the moment the doctor picked you up off the delivery bed and hurried across the room.
"Wait," I say, "aren't you going to give the baby to Kathy?"
"Not now," the doctor says, his normally soothing voice suddenly businesslike. "He's having some trouble. We have to give him a little help."
Your heartbeat on the monitor was so strong minutes before, during the late stages of your birth; now you are the wrong color, and your arms and legs flop lifelessly in the doctor's hands.
He lays you on a table, and you're quickly surrounded by other doctors and nurses. Your mom refused all drugs during labor because she wanted you to pop out into the world bright-eyed and alert. Now I hear a nurse say, "He's not responding."
There are several sharp slaps. Quiet, urgent discussion. Someone says something about a "jump start." I clutch your mom's hand. I feel as though someone is holding a gun to my head and demanding something I can't give.
Until then, everything had gone so well. Your mother and I had all kinds of tests. Everything looked excellent. In the sonogram, you not only seemed normal and healthy, but it was obvious to us that you already had immense personality and charm.
As we went to work preparing for your arrival, we felt as if we knew you. Your brother, Mike, at 11, informed us that he was the one who would be your official instructor in life's fine arts: baseball, electric guitar, being a boy.
From the moment she knew she was pregnant, your mother went into super nutrition-rest-exercise mode. If you wonder why you're a James Taylor fan, it's because she sat at the piano many times and sang you "Sweet Baby James."
Then the big day, and the bad moment. During your development you had tied a knot in your umbilical cord, a loose knot that snugged up tight during the final stage of birth and shut down your oxygen. For how long? You tell us.
Our world moved in horrible slow motion as the doctors and nurses worked on you. Suddenly, somehow -- a tiny, squeaky protest. A twitching of arms and legs. You were alive!
"Everything looks good," says the doctor in the intensive-care nursery, where you spent your first three days. "As far as we can tell from the blood tests, his oxygen wasn't shut down long enough to cause permanent damage. But there's no way of telling for sure right now."
When would we know? Sometimes damage doesn't show up for weeks or months, we were told. Eighteen months, one book said, maybe more. In tying that little knot, pal, you forfeited the standard factory warranty against defects in parts and labor.
Now you understand why we made such a fuss over your first smile, your first words, your first steps, and today your first big-boy walk down the stairs.
No, your mom and I didn't become raving paranoiacs and hand-wringers. We didn't feel that God owed us a flawless child -- especially after spending so much time in that intensive-care nursery, where some of the babies were no larger than newborn kittens, and some were already injured beyond repair.
But we did develop what you might call a heightened sense of awareness. Without much talk or fuss, we make it a point to know when you are supposed to do things. We eagerly anticipate those moments, and savor their arrival.
And we refuse to let worry overcome wonder as we watch you develop. It's as if a tiny workman is in your brain, flipping on switches.
Now you're almost 2, and our concerns have all but vanished. But I hope they never disappear completely. I don't want to take it for granted when you hit your first home run, play your first notes on a trombone, or drive off on your first date. The memory of those terrible few minutes on the day you were born will always be there.
And it serves as a reminder of just how lucky we are.
Scott Ostler is a columnist for the San Francisco Chronicle.