how to lie to your children--and feel bad doing it

I've recently been put in the position of having to tell my children an untruth--to protect them from the ugliness of the world.  I don't like it.  I am usually very honest and open with my kids, but how do you explain violence to a four and two year-old?  How do I tell them my heart is heavy for my friend and their friends without tainting their world?  I don't know.  But my heart is heavy.  And I fear for my friend.  I hurt for her.  Someday, I will tell my children about people who bully others because it gives them a feeling of power.  I try to show my children the importance of respect for everyone.  I teach them to love as Christ commanded, to say sorry, to forgive, and to forget wrongs.  I try to teach them to stand up for themselves.  I hope it's enough. 

Be safe, my friend.  Be safe, little M and little A.  Be safe, big M.