Imagine you are a child.
A new pupil joins your class. Because you have been brought up to be kind, or because you have been new yourself, you befriend the new kid. You share your playtime snack, show them the ropes in the lunch hall and at the end of the day, give them the present of a nice pencil you have that's only slightly used.
Over time, you become good friends, and the day comes when you are invited for a play date. Your parents make the arrangements, and you turn up at your friend's house at the appointed time. You are astonished to discover that your new friend is clearly fabulously wealthy. The house is a mansion, there are horses and an indoor swimming pool. Everything is decorated in the most beautiful taste.
You gaze around with your mouth wide open. "You're...rich!" you blurt out.
"Well, my dad is."
"Why didn't you tell me?" you say.
"Well," your friend says, "it's like this. I have been in other schools and somehow everyone found out who my father is. Everyone wanted to be my friend but I didn't know if they liked me or just the fact that my dad is rich. So when I moved to this school, I changed my name to my mum's maiden name. I made the chauffeur drop me off a few streets away. I got cheap clothes. And you know, you were the only person that was nice to me and became my friend. So I knew that you cared about me and not the fact that my family is wealthy. I knew I could share the nice things we have and you would still care about me as a person because you cared about me before.
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Check back next week for the explanation! Or work it out yourself!