Was that a real baby smile or just wind?

She smiled several times in the incubator

That's how the question was actually asked. Does she know what she's doing when she's smiling, because she did it several times in the incubator today.

It was in the middle of a much longer conversation about her weight, about when they'd introduce breast milk, and about everything we needed to know before she came home. And in among all of that, the smile is the thing we stopped to ask about.

The scientific answer

Early smiles are usually spontaneous rather than social. In the first weeks they tend to happen during sleep, or as movements that aren't yet aimed at anybody.

The deliberate one — the whole-face, directed-at-you smile you can get her to do again — usually turns up somewhere around six to eight weeks. It's unmistakable when it happens.

Count from her due date, not her birthday

This is the part that saves a lot of unnecessary worry and nobody explains it well.

Ari was born in July at 33 weeks and was due in September. For early milestones like this, corrected age is counted from the due date rather than the birth date. A baby born seven weeks early may reach a milestone seven weeks later and still be right on track.

We asked whether that gap closes or stays. Corrected age can remain useful for the first two years, then it gradually stops mattering. Knowing that earlier would have spared us a few worried evenings.

Why the reflex ones counted anyway

Here's what we'd say to anybody arguing with themselves about whether it was real.

You smiled back. You talked to her. Your voice went up. You leaned in closer to a plastic box to get a better look.

She may not have meant it. The thing it started was real, and it was happening weeks before she could do anything about it on purpose. That's not sentiment — it's how the whole business gets going.