Ahem. 
Well, yes. We must somehow stop a bastard from acting like a bastard. If the jerk does something like this to a child, they must be stopped. I would prefer we get to mash their balls to paste so they never get to abuse another child again from their own progeny but I KNOW that's wrong. lol.

But in all seriousness, there's nothing wrong in giving them some sort of physical pain equal to what they've done to a child, or at least close enough to it so that they won't harm them again. You could, for example, cane them the French way, until their ass cheeks are almost sliced off lol. One thing that is possible is that a perpetrator only succumbs to a moment of lunacy and/or idiocy once, and never does their crime again. In that case, perhaps very light corporal punishment and a fine is good. If they are repeat offenders, the said child must be given to the custody of a compassionate person, and the "Father" or whomever abused the child should be punished severely. Not necessarily permanently, but in a way which is very hurtful to drive home the point that they are being punished and WILL NOT abuse children again, or ELSE!

Something like this should be done for non-Parents, just abusers in general as well.