It's taken me a while to respond to your latest question because I'm not sure where to start. To simply answer why I think God allows children to hurt, be hurt, get sick or even die doesn't seem the right thing to do. Because the answer sounds way too simple without some major theological foundations being put out there first.
I mentioned the "mean dude" in a previous post. I talked about believing that evil exists and I believe also that because of free will, God has allowed us the freedom we think we want. And then we just go on ahead and totally wreck the place. So things like cancer or hydrocephalus are a result of what you'll hear Christians call "a fallen world."
That's all I'm going to say because I think that maybe we should talk a bit more about this. What do you think about it? Do you think God causes the bad things to teach us lessons? Or do you think maybe that stuff isn't from Him? What other questions does that bring up?
I think if we talk more about this, the answer to your question about children being hurt might become more clear to you. Not that our human minds can EVER make sense of the injustices done to children, I don't believe we're supposed to be comfortable with that, but maybe we can understand a little more that God's role in it is always love.
Take your time and throw more questions out. I'll make Midnight Cafe answer them :)