"Do you know why Xiao Ming's grandma can live to be 99 years old?"
"Why?"
"Because she doesn't mind her own business."
"But Mrs. Sun next door lived to be a hundred years old."
"..."
"She is the exception."
In the unit story, Mrs. Sun's cp is the original wife, and there will be no cp in the small world.
Purpose: If you mind your own business more, the world will be better.