When Do Kids Realize They’re Going to Grow Up?

This video is so cute it actually hurts a little: A 5-year-old girl named Sadie loses her mind upon realizing that her beloved baby brother will not actually stay a baby forever. “OH MY GOSH! I want him to stay little,” she wails. Soon, her concerns shift from her brother to herself and her own mortality: “And I don’t wanna die when I’m a hundre-e-e-e-e-ed!” 

Judging from the tiny girl’s shock, it seems like it’s the first time she’s fully grasped the grim realities of aging and death — which brings up some really interesting questions about psychology and child development. When do young children start to figure out aging, and what do they understand about it?

Research suggests that kids do understand that they’re going to grow up — but they also misunderstand the mechanics of the aging process in the most adorable way possible: According to a study by Israeli researchers Rama Klavir and David Leiser, children between the ages of 3 and 5 seem to think that birthday parties cause aging.

The researchers asked about 100 kids, ages 3 to 9, a series of questions to gauge their understanding. In one of the questions, they described this scenario to the children:

A child’s birthday was celebrated when he was 1 year old. Then when he was 2, they celebrated his birthday again; and the year after, when he was 3, they also celebrated his birthday. But the next year, the year after he was 3, his mother got sick and could not give him a birthday party. So he was very sad because he did not know how old he was. In your opinion, how old was he?”

Some of the youngest children, all under 5, gave answers like, “He will still only be 3 years old because he didn’t have a birthday party” and “If next year he won’t have a birthday party? He, he—he won’t grow up.” Then, the researchers told the children that the mother in the story felt so bad for being sick on her son’s birthday that she gave him several birthday parties to make up for it. The answers from the littlest kids in the group again hinted at the magic of the birthday party: They thought that if the child had multiple birthday parties in a year, his age would increase accordingly.

I know. I know. It’s so cute I can’t stand it, and neither could Jacqui Wooley, a psychologist at the University of Texas, who was curious to find out more about what small children believe about the aging process. In a not-yet-published study, Wooley and colleagues interviewed about 100 preschool-age children, and found that, apart from their childlike beliefs about the magical powers of birthday parties, young children do seem to grasp the basic premise of aging. “It seems like they really understand that people age, unlike the girl in the video,” she said. “So they should understand that people age by the preschool age.”

And this is actually a fairly new way of thinking about what children understand about growing older. As Wooley explained, the traditional view of child development still borrows heavily from the work of Jean Piaget, the famous Swiss child developmental psychologist. “According to Piaget, kids wouldn’t understand a lot of this stuff, but researchers in general are finding that children know a lot about people and animals and growth and biology – and even death,” Wooley said. So maybe they get some of the details wrong, but they do know a lot more than we give them credit for, in other words. 

I think that, in general, our lay culture hasn’t caught up with the research yet, so we still don’t talk to kids about death — we think they aren’t emotionally ready to handle it,” Wooley said. “But the recent work shows they do actually, by preschool years, they do understand certain, basic things about death.”

All of which suggests, Wooley explained, that the little YouTube girl’s freak-out may not be a matter of her suddenly realizing that she and her baby bro are going to grow up; it could be that she gets it, and she’s just sad about it. “My guess is that she can easily understand that people grow up, but being forced to think about her cute little brother growing up is making her sad, just like it might make her mom sad at the thought of her little baby growing up,” Wooley said. And, anyway, nobody likes thinking about dying, whether or not they reach a hundre-e-e-e-e-ed

When Do Kids Realize They’re Going to Grow Up?