Imagine if all you had to do to avoid getting a year older was to not have a birthday party. Simple, right? It turns out that a good number of young kids think these parties are what makes us older.

In a study of 99 kids aged 3, 4, and 5, nearly two in five of the youngsters thought that birthday parties were somehow linked to ageing. Don't have a party, and maybe you can stay the same age.

While the older children seemed to have a better grasp of age and how we get older, the confusion over the link between parties and moving up a year was spread across all of the kids – which is understandable, as they suddenly find themselves one year older after blowing out candles on a cake and singing Happy Birthday.

"Results indicate that young children understand certain important biological aspects of the ageing process but exhibit confusion regarding others, including the causal role of the annual birthday party," write the researchers in their published paper.

Jacqueline D. Woolley from the University of Texas at Austin, and Amanda M. Rhoads from the Community of Hope in Washington DC, ran through three stories with their young volunteers to explore how they understood ageing.

The first story was about a kid who didn't get a party, the second was about a kid who got two parties, and the third was a more general, control story about a child turning 3.

Nearly 20 percent of the toddlers thought the lucky child who got two parties would be two years older; meanwhile, around a quarter of the kids thought the child in the no party story stayed the same age. A repeat of the study with a different group also produced similar results.

A previous study has shown this way of looking at parties as the causes for ageing can last until kids are 6 or 7 years old, though that earlier research wasn't as specific in the questions it used – instead the children were polled on whether having multiple parties to try and get older was "a good idea".

Of course, even though these results are fascinating, the relatively small sample size and the fact more than a quarter of the kids got the control question wrong, makes us cautious about drawing any major conclusions here.

But we can't imagine a much cuter concept than staying the same age until the cards and presents are rolled out - and why wouldn't young children think this way?

The effects of ageing are largely imperceptible to little minds, and then in a flash and a flurry of jelly and ice cream they're a year older.

For the current study, the youngsters were also told a story about a woman who didn't want to get older. More than 70 percent of the 3-year-olds thought adults could avoid ageing if they so wished, though this dropped sharply with the 4- and 5-year-olds.

And perhaps this shouldn't come as a surprise either, as us grown-ups spend so much time talking about wanting to look and feel younger.

The researchers behind the study say it's an important look at both how we come to understand the passing of time, and how much significance our society gives to birthday party celebrations, especially when we're little.

"Anyone who celebrates birthdays or who wonders about children's minds should be interested," Woolley told George Dvorsky at Gizmodo.

"Our culture is obsessed with the concept of the birthday party. Parents should enjoy their children and their children's questions, and discuss these issues with their children as they arise spontaneously."

The research has been published in Imagination, Cognition and Personality.