Relax, folks – the nappy changes, tantrums, talking back, and anxious evenings are all worth it in the end.

Researchers have crunched the numbers on the life expectancy of both parents and non-parents, and found having at least one child can stave off death for at least a year or so in your old age – an effect that becomes more pronounced the older you get.

We’ve known for some time that having kids seems to make you live longer, especially if you have them early in life.

What nobody knows is why this happens, so a team of researchers from Karolinska Institute in Sweden broke down the statistics of elderly parents and analysed how having a child affects a person’s chances of seeing another birthday.