Short but significant story

I got this in an email from friends of ours from our former church who read our blogs. Thanks, D!

I was reading a Reader's Digest at the eye doctor's office last week, and found a short item about a mother who was having trouble with her child. The girl locked herself in her room and would not communicate. In the morning she opened the door and found a wrapped rock by it with a note: "this rock is 300 million years old. I will love you and forgive you that long."