You're missing nothing, and there's not much reward. In fact, with the GroTo pack, the feeding infants in the high chair to learn their fav foods is behind many many milestones. It's arguably the cutest part about infants, and I only did that once. And that was before getting the pack. Now... it's just too out of reach behind too many milestones. When the infant is clearly going to get the top trait, I age them up. This is always before they can even crawl. There's nothing lost by doing this, I try to play with infants as little as possible. As a game system, it's very weak / non-existent. It's a prop for roleplay.
Children get 4 aspirations which maybe have more impact on a sim.
