Why Does God Allow Bad Things to Happen?

During school today, I was able to give my children a better understanding of how this question can be addressed.  I'm sure that at one time you have had an unbeliever ask you, "Why would a loving God allow bad things to happen?"  I have and most the time my answer has been, "Who are we to question God."    Although I don't have all the answers, I can tell someone that's asking this question that their thinking is wrong and use this following explanation to help them see how.

A loving parent raising a child will instruct them on many things.  One day, the child might reach up to touch a hot burner on the stove and the parent, seeing them, would stop them and explain the dangers of touching the stove and teach them to stay away from the stove.  Being quite sure that the child understood the instruction and dangers, the parent would believe that the child would no longer want to touch the burner.  But, if the child later decided to go against what the parent has taught them, not trusting or believing the parent and burn himself by touching the burner, who is to blame, the parent or the child?

I know that sometimes this explanation isn't an easy fit for each scenario, but the idea that when someone chooses to NOT believe in God, or disregard and go against God's instruction and the consequence leads to hurt, pain, or worse; eternity in hell, who is really to blame?  I also know that it is hard to explain that some people get hurt by the sin of another person, but it is also the consequence of one person going against what God commands.  So who is to blame?  God or man.

God has made it very clear to us in Romans 6:23.

"For the wages of sin is death, but the gift of God is eternal life in Christ Jesus our Lord."

And then there are times when we have to say, "Who are we to question God?"  
Such is the case of a couple I just read about who has just lost their second child (the first on at 7 mos. old and a year or so later, a second one at almost 8 mos. old).
This really hit me hard since, on the day I am celebrating my son's 13th birthday, I realize that another person is experiencing the loss of a second son.
My only hope is that as believers, they understand Isaiah 55:8-9 8
"For my thoughts are not your thoughts, neither are your ways my ways," declares the LORD. 9 "As the heavens are higher than the earth, so are my ways higher than your ways and my thoughts than your thoughts."