Labels for Laibel, by Dina Rosenfeild.

Every child learns from a young age that they have to share. Some children learn this through interaction with younger or older siblings while others learn it through playgroups and school. Either way, most children eventually learn that it is expected of them to share with other people.
In a family, the older sibling usually has trouble sharing at first. They were the only contender for their parents love and when a new child comes along, that is all changed. They usually are resistant to sharing with a younger child and make sure the younger child is aware of what is off limits; they…