In the story, A Christmas Carol, when Fan comes to pick Scrooge up, we learn a reason why Scrooge may have turned out the way he did, what is this reason?

Scrooge has been shoved aside by his family and ignored. Fan is the only one he can depend on for love.... she loves her brother and has no problem showing it. Sadly, without her, he has nothing. He's learned to fend for himself, and for the most part, by himself.