Your statement is flawed. If God can't preclude rapes of children from our world, then it MUST follow that he can't do anything - as there is something he can't do. If he could do anything, then he would be able to preclude rapes of children from our world.
If God exists, he either:
1) Can prevent children from getting raped.
2) Can't prevent children from getting raped.
If #1 is true, then God must be choosing to not prevent children from getting raped.
I don't quite know what you mean by "doesn't care". If God is capable of preventing evil but doesn't, it follows that he doesn't care enough to prevent evil.
And how can we know what "all evil" means?
What we do know is if God is capable of preventing children from getting raped, but chooses to not prevent the rapes, then it follows that God doesn't care ENOUGH to prevent the rapes.
I can only go by what I observe. Rapes of children are occurring. Christians maintain that their god exists and can do anything. Since an all-loving, all powerful god can't exist in the presence of mass calamity, then we know with 100% certainty that either your god - if he exists - either can't do anything or doesn't care ENOUGH to do anything.