Can babies sense your unfair play with them?

Children as young as 15-month-old possess the basic sense of what is fair, researchers have found.

A study has found how the children noticed the difference between the equal and unequal distribution of food or drink and reacted with surprise to perceived unfairness.

That altruistic awareness and concern for others was also linked to their willingness to share a toy, it added.

According to Jessica Sommerville, who led the study, "the findings show that these norms of fairness and altruism are more rapidly acquired than we thought".

During the study, it was observed how babies watched videos of crackers and milk being shared out.

"The infants expected an equal and fair distribution, and they were surprised to see one person given more crackers or milk than the other," said Sommerville.

The kids were also given two toys from which to choose in the University of Washington study, the findings of which were ­published in the journal PLoS ONE. 

It was found a third of them were ready to share their favourite toy, another third shared their non-preferred one, but the final third did not share.

"Babies who were more ­sensitive to the fair distribution of food were also more likely to share their preferred toy," the study's lead author added.