While imitation may be the sincerest form of flattery, it seems it's only a fluke if a baby copies your silly facial expressions.
For decades, new parents and scientists have believed imitation is an inborn capacity in humans.
But University of Queensland and international researchers failed to find any evidence that very young infants are capable of imitation.
Their study, published in Current Biology, involved 106 babies who were presented with 11 examples of facial expressions, gestures or sounds created by both human and non-human models.
They were tested at one, three, six and nine weeks of age.
The categories included poking out a tongue, mouth opening, happy or sad face, pointing a finger or making a clicking sound.
"The results provided evidence against the view that certain human behaviours are innate," said the university's Professor Virginia Slaughter.
The babies were just as likely to respond with a random gesture as they were to copy one.
"Human children in later stages do copy others actions, but the controversial assumption that this occurs from the moment of birth needs to be rethought," she said.
The researchers say the limitation of previous studies involved them only testing the response to two gestures, tongue protrusion and mouth opening.
No additional gestures or expressions were made to see whether infants were truly imitating the adult's behaviour.
"If infants also increase their tongue protrusions when an adult models a happy face or finger pointing, then it's not a case of imitation, but probably excitement at seeing an adult do something interesting," said Prof Slaughter.