Parental love really does blind mothers and fathers to the sins of their children, new research suggests.

A study found that parents spot lies told by the offspring just one time in ten, compared with strangers who pick up untruths more than 40 per cent of the time.

Researchers at Brock University in Ontario, Canada said the research showed that parents had an inherent ‘truth bias’ when it came to their children, believing youngsters were far more honest than they actually were.

To carry out the experiment 72 parents were asked to rate video-recordings of their children either lying or telling the truth. The same videos were then played to childless undergraduates and a separate set of parents whose children were not involved in the experiment.