Gawd, if someone hurt my children I would wish them all manner of harm. I would probably want to mete out that rough justice.
BUT how many parents/relatives of children/family members who are affected like this show enormous dignity and use their anger for good? I'm thinking Sarah Payne, Sophie Lancaster's Mother here. It seems like some sort of switch happens and people want to honour their child's/relative's memory instead of stooping to eye for an eye level.
It always amazes me in all honesty. I am very hotheaded and cannot imagine not wanting to harm beyond all measure someone who had harmed one of my family. I guess the numbness and emptiness leads people to fill that void with something positive and fitting for their loved one's memory.