Parenting is a thankless job. Not only do your children take up all your time and money, grow up and then leave you at home (or at a home), now you get stupid as well!

Head of study, Dr Hosung Lee said: "It explains why parents think their kid is the smartest in class or the best athlete, even if that child is as dumb as a box of rocks or needs a calendar to time a 100-yard sprint."

A real life Becker.