Parents often feel it's their responsibility to teach children fairness, but studies are illustrating that children instinctively grasp social rules and fair play.Toddlers as young as 19-months-old expected fair play and expressed concern when that didn't happen in a study conducted by child psychologists at the University of Illinois Urbana-Champaign.This research confirmed results from similar studies conducted last year."These studies, like earlier studies, show that children have expectations that individuals will distribute resources and rewards fairly," said Renée Baillargeon one of the authors of the study.In two separate experiments, scientists engaged 19-21-month-old children in scenarios in which puppets earned rewards or gifts.In the first experiment, researchers put on a "show" for 48 children where two giraffe puppets were given toy ducks, edible cookies or toy cars. Children sat on their parent's lap as experimenters gave items to the puppets with either equal or unequal distribution.In a second experiment, children observed (again while sitting on a parent's lap) as a researcher told women playing the parts of kids to put away their toys. Some of the children could explicitly hear that there was a reward involved (a sticker) while, in another case, the researcher never mentioned a reward. One of the "lazy" individuals playing would intentionally not pick up the toys but still receive a sticker because experimenters wanted to see if children expected equal gifts for equal work.After observing the children's reactions researchers found some surprising results.Children in both situations spent more time focusing on unequal distribution of items or tasks, leading researchers to conclude that they usually expected fair allocation of objects, presumably trying to figure out what went wrong.The sense of fairness observed in the toddlers can be traced to two plausible sources, according to the study. On one hand, babies could have developed a sense of altruism as a way to adapt to group life.Scientists hypothesize that, early on, man lived in small groups and each member acted in the best interests of the group, including young children, Baillargeon said. Another equally plausible explanation is that children merely have learned fairness by observing encounters in their environment.Though the results seem only to suggest that humans have innately good intentions, the results may have larger implications for understanding human development."If children come to us with expectations, it may affect how we react to children retaining norms," Baillargeon said. They're not just picking up the norms they have already been taught, she said. "It could affect the way we teach what is appropriate behavior."Even with natural altruism children can exhibit selfish behaviors, particularly when encountering others in school, Baillargeon said. This contradictory behavior often arises because infants and toddlers understand their own needs."Babies also have a strong sense of self-preservation," Baillargeon explained. "The general expectation of fairness does not mean that they will act fair in all instances. There are times when they want all the cookies. Some cultures will emphasize some thoughts and others will de-emphasize them."Cultural norms and expectations can often dictate behavior, which is why not all families or groups value fairness in the same way, Baillargeon said. Family and culture may reinforce or redirect the child's initial impulses for fair play and survival.Along with developing a more detailed picture of how children develop, this research also sheds light on the effects of abuse. Rather than learn from the abusive behavior, children can have their concept of the world shattered."Negative experiences in childhood may have a negative impact," Bourgeois said. "It is a deep violation of your expectations and can really influence your view of the world."