We all like to think our kids are the kindest, most generous children in the whole wide world – a credit to the genius of our parenting skills.
But wait until your your back is turned - and they turned into selfish little monkeys who would rather chew off their right arms than share their sweets or toys with another child.
That's the conclusion of some new research which revealed that kids as young as five are only generous when they are being watched.
According to the study by Yale University, children make strategic decisions about when to behave generously. And - surprise, surprisie - they are only generous when others are aware of their actions.
The authors said that, just like adults, children behave in ways that enhance their reputation when they are being watched but not in private.
The research, published on Plos One, presented five-year-olds with stickers and gave them the option of sharing one or four stickers with another child the same age.
They found children were more generous when they could see the recipient than when the recipient was hidden from view.
They were also more generous when they had to give stickers in a transparent container rather than an opaque one, meaning the recipient could see what they were receiving.
Lead researcher Kristin Leimgruber said: "Although the frequency with which children acted antisocially is striking, the conditions under which they chose to act generously are even more interesting and suggest that children likely use much more sophisticated pro-social strategies than we previously assumed.
"Much like the patterns of charity we see in adults, donation tendencies in children appear to be driven by the amount of information available to others about their actions - for both adults and children, the more others know about their actions, the more likely they are to act generously."