Toronto, Canada, October 23, 2008 -Can you imagine three months old babies feeling the emotion of jealousy? A new Canadian study suggests that babies can exhibits signs of jealously even before they start crawling or say sit up on their own.

The finding of the study contradicts earlier developmental theories which say that infants develop complex emotions such as jealousy during what are called 'terrible twos'.

Lead author of the study, Prof. Maria Legerstee, professor of psychology at York University in Toronto, Canada, says even three months old baby may have ways of letting mom know by crying, kicking and turning in their seats when mom's attention turns to someone else. She says the behavior is quite normal and parents need not worry about it.

"It's a normal and appropriate reaction," Legerstee said.

The team led by Prof. Legerstee studied nearly 50 babies of ages three, six and nine months who had their mothers at hand while a female researcher interacted with them.

Prof. Legerstee said when the mothers interacted with the babies they smiled and gave happy expressions but when mothers did not interact with them they smiled less, seemed unhappy and looked away. But when she was busy taking a drink and did not engage in conversation, babies did not mind.

In the second part of the experiment, when the researcher talked to mothers in monologues, the babies did not seem to mind. However, when the female researcher got engaged in active conversation with infants' mothers, laughing and deliberately excluding babies, they behaved in a way that researchers had never seen before in their research and were quite surprised.

Babies "kicked their legs, yelled out loud and turned in their seats," Legerstee said and added, "I've never seen anything like it."

The development of "non-basic" emotions such as jealousy, pride, embarrassment and guilt are thought to develop during the second year of life, generally known as terrible two's, Prof. Legerstee said.

She added, "The established notion was that an emotion like jealousy is too complex for the basic cognitive abilities of infants." Prof. Legerstee's study is a part of a series that are looking at socio-cognitive development in babies.

The findings of the study will be included in next year's Handbook of Jealousy: Theories, Principles and Multidisciplinary Approaches.