Our three year old grandson and his mother were looking at a kids Bible Story book. He really wanted to know why people would do such an awful thing....kill Jesus. That started a conversation which explained that Jesus loved everybody in the world so much that he died to forgive all the bad things that they have done. In simple faith he asked Jesus to forgive his sins and come into his heart & life. :)
Matthew 18: 2-3 Jesus called a little child to him and put the child among them. Then he said,"I tell you the truth, unless you turn from your sins and become like little children, you will never get into the Kingdom of Heaven."
The next day he was playing lego with Grandpa, and looked out of the window and said, "It's a beautiful world." He noticed the bright sunshine
(yes, indeed! we have seen the sun) the colors of the blue sky,
the fresh yellowy green leaves of the locust tree and the
red geraniums in the window box.
After a few moments he asked, "Why are there bad people in the world?" In his little mind the two things just didn't go together.
It's hard for me, as an adult, to comprehend why people find twisted pleasure in causing suffering and heartache, ruining and destroying such beauty and tranquility by their evil deeds & selfishness, all for a few moments of temporal power or wealth. Try to explain that "Why" to a deep-thinking, little three year old kid.