HN people are overachievers... So invariably your approach to child rearing is going to be reading a lot and being informed. It's helpful to do so to know what's coming. But in reality you don't need to. A lot of learning will be on the job.

Yes, your free time disappears completely. But there is an upside. Watching a human being grow and learn is fascinating. Plus that human is a part of you in a sense. That is also beautiful and hard to describe in words.