A mother spoke of her concern about her daughter’s interactions with a visiting playmate. The play broke down because her child was upset each time the visitor wanted to play with something of hers. “No, mine,” her child protested when one of her toys was used by the other child. Mom was upset about what she saw as a problem with sharing and wondered how to handle such situations.

This question often comes up in pre-school groups when two children may get into an altercation over both wanting the same block or toy. Sometimes one child will take another’s toy and the teacher misses the protest. Later on, that child may express his anger by getting back at the aggressor.

Observing in a group where the children were playing with an assortment of cars and animal figures, a boy sitting at the edge of the group, looking around to make sure no one was watching would take one of the objects from the pile and quickly put it on the floor behind him. He didn’t actually play with them — just seemed intent on collecting and saving them for himself.

Learning to share is a big developmental step, an aspect of social behavior that adults react to because it impacts on others and is therefore judged critically by adults as “not nice.” It is as though this behavior reflects poorly on the parents. But with children entering groups at younger and younger ages, the expectation for sharing behavior often precedes the developmental ability for such behavior.

Sharing possessions involves the concept of yours/mine, you/me. In other words, it means awareness that one is a separate individual, not connected to someone else. Babies are not born with that awareness. Psychiatrist D. W. Winnicott is quoted for saying “there is no such thing as a baby,” meaning that an infant is connected to a mother/caregiver for survival. The human infant is unable to survive on its own.

As babies grow, increasingly they become aware that they and a caregiver are not one and the same. This has been called a period of separation/individuation and is related to increasing independent functioning such as walking and verbal communication. This beginning independence is both exhilarating and scary. You can assert your own will but at the same time separation means risking the loss of gratification that comes from mother or caregiver.

Possible anxiety about separation gets expressed in a variety of ways, one of which is connection to one’s possessions. Another child taking a toy to play with evokes a sense of loss, which in a sense has nothing to do with the other child or the toy. Being reprimanded for “not sharing” exacerbates the situation and often provokes a more intense protest and upset.

Some cultures reject the idea of an investment in personal property and discourage the idea of “yours” and “mine.” Our society, however, which values individualism and personal property, nevertheless considers generosity and a willingness to share as desirable traits and labels their absence as “selfishness.”

Awareness of the developmental meaning of a child’s cry of “mine,” gives us some ways of responding to the upset. You can prepare a child ahead of time for the reality that her friend may want to play with her things but also acknowledge that there are some things she may not want to share. Best to put those away in the closet before the other child’s arrival.

In teaching a child the value of sharing it helps to also appreciate the wish not to share — a wish shared by all one time or another.

— Elaine Heffner, LCSW, Ed.D., has written for Parents Magazine, Fox.com, Redbook, Disney online and PBS Parents, as well as other publications. She has appeared on PBS, ABC, Fox TV and other networks. And, she blogs at goodenoughmothering.com.