There is no fundamental difference between creating a strong AI and having a child.
I disagree, though some of it depends on exactly how you create the AI. A child is a machine optimized for serving the "interests" of its genes (half of which it copied from you), and even in the near-future of say "Gattaca" you don't really have much say in how the child works. Even if AIs were grown in a biological analog, the initial inputs would be totally different than anything else in Earth history, much less arbitrary (from our idealist viewpoint) than what goes into making up a person. Even if you set them up to evolve in a biological manner, where the inputs eventually drifted, their "genes" certainly wouldn't be anything like oldschool life genes, much less human. Perhaps you'd get some interesting convergence, but that's not the same thing.
To see the potential of AI, you really need to think like a god, not a biologist. Or possibly somewhere in between the two. Imagine what life on Earth would be like if the creationists were right, and you'll get an analogy of how AIs might end up. (Better yet, think like HPL's elder things, and consider the shoggoth.) Whatever they have in common with previous life would be remarkable exceptions, and most of it would be new and alien-like. I think they're be more alien than "real" (biological) aliens.
Maybe think of AIs as (initially!) part of humanity's extended phenotype, like a spider's web is to a spider, or a dam is to a beaver. Could you convince a spider that a web is like its child, the new spiderdom of the future? I don't think a web that can "do things" would make your argument to the spider any stronger.
I'm not saying you should freak out, but They Will Not Be Humanity.
And most of what I'm saying is from taking a fairly extreme biological view. I wonder if that's kind of outdated, and AIs are going to be even less like life, than predicted in previous decades.