Amber Minogue

The researchers looked at studies of other mammals, like cats, dogs, mice and squirrels, all who, like us, have babies who are helpless at birth.

Studies of these animals showed that when mothers carried their young, they became calmer.

This effect is called the transport response and may have developed because animals often move their young to avoid danger.

And it seems the same might be true of humans.

The team monitored 21 babies and their parents interacting using heart monitors and video.

They made note of four different approaches to soothing a crying child.

Holding them while sitting, putting them in a bed, holding them while walking or rocking them in a pram or chair.

They discovered that movement was key and that only babies being carried or rocked were soothed.

Being put in a bed or even being held but not moving did nothing.

After five minutes, all of the babies stopped crying and most of them had fallen asleep.

But, as all parents know, you cannot just put your baby down as soon as it's asleep.

And the researchers agree.

A third of babies would wake up again immediately if placed in a bed.

So how do you get the baby to sleep?

Here too, science can help us.

The heart monitors showed that the moment the physical contact with the parent was lost, the baby's heart rates would increase enough to wake them up.

And so lying them down, even really, really,

really slowly, just did not work.

Well, as the researchers acknowledge, a study of 21 babies is just a beginning and further research is needed.

There you have it.