Parenting is an elusive art. Nobody feels like they've "cracked it".
And yet, some people seem like naturals.
Cynics might say they're faking it. In the past, scientists would have said they'd learned nurturing instincts from their own parents.
But a new study by Harvard University offers another explanation: they were born that way.
According to research published today, some people carry a "nurturing gene", making them destined to be a good parent, the Daily Mail report.
It is the first study to suggest that parenting differences lie in genes and not experience.
Previously scientists believed that our parenting styles depended on how we were raised. For example, those who had attentive parents were expected to be attentive parents themselves.
The study, conducted at Harvard University in Cambridge, Massachusetts, used two species of mice: the deer mouse and the oldfield mouse.
Researchers created a behavioural assay to track the behaviour of both males and females of each species.
It also measured how often they engaged in parental behaviour such as building nests and licking and huddling their pups.
The data found that the females of both species were attentive mothers but the same didn't hold true for the males.
Oldfield mice fathers are relatively involved in raising pups, as much as Oldfield mothers, but deer mice fathers participated relatively little.
To test what impact those different parenting styles had, the team performed a cross-fostering experiment.
Oldfield mice parents raised deer mouse pups, and vice versa, and the parenting behaviour of the pups was observed when they became parents themselves.
"What we found was there's no measurable effect based on who raises them," says Dr Hopi Hoekstra of Harvard University.
"It's all about who they are genetically. The other significant result here is that there are some regions that affect multiple traits and others that have very specific effects.
"For example, we found one region that affects licking, huddling, handling and retrieving, but another that affected only nest-building."
The researchers looked at locating individual genes that might be linked with parental behaviours.
They studied the hypothalamus, the region of the brain known to be important in social behaviour.
Almost immediately, one gene for the production of vasopressin (a hormone produced by nerve cells) jumped out at them.
To test whether vasopressin actually affected parental behaviour, doses of the hormone were administered to male and female Oldfield mice, which saw nest-building behaviour in both dropped.
For future research, the team would like to look at the neurological circuitry involved in parental behaviour so they can target specific genes.
"This gives us molecular handles to start understanding the circuitry much better,' said co-author Dr Andres Bendesky.
"We can see what is happening in the brain, not in the abstract...but we can say vasopressin is going from this part of the hypothalamus to this other part of the brain, so we can see how the brain is organised."
This article was first published on Daily Mail and is republished here with permission.