How Youngest Child Syndrome Shapes Development

Are you the "baby" in your family? If so, you might identify with youngest child syndrome. Youngest child syndrome refers to the characteristics and traits of being the youngest child in a family. While youngest child syndrome is not an official diagnosis or condition, research has been done on the birth order of children in the family construct. 

When scientists look at personality in adulthood, Julia Rohrer, personality psychologist at Leipzig University, says that they mostly find no systematic differences between firstborns, middle children, and lastborn children with respect to major dimensions of personality, such as emotional stability, extraversion, agreeableness, neuroticism, and openness to experience. 

However, common characteristics and traits have been found. 

“There are some that are associated with being the youngest child in a family (such as being risk takers, being spoiled), but there is little evidence that confirms such stereotypes,” says Rohrer. 

Characteristics of Youngest Child

Some common traits and behaviors associated with the youngest children include:

• Risk-taking
• Entrepreneur mindset
• Prosocial
• Resilient
• Being spoiled 

Research from the University of Birmingham and the University of Reading found that the youngest children in families who are not self-employed are nearly 50% more likely to take the risk of going into business. The findings were based on analyzing traits of more than 17,000 children born in 1970, who were surveyed again at 38 years old.

Another study found that the youngest children had the lowest rate of mental health challenges, including emotional, conduct, and attention problems. 

Rohrer says of all the research conducted, scientists consistently find small effects on intelligence in samples from the global north. “Firstborns are a little bit smarter, and then on average intelligence declines with birth order position,” she says. However, she adds that these effects are small on average and not deterministic.

“So, in any given family, the youngest child may actually be the smartest. Just when we average across thousands of people do we detect that on average, firstborns are a few points smarter,” says Rohrer. 

“[We] know that personality matures and within a family, the youngest child may end up with the ‘least mature’ personality just by virtue of their younger age,” says Rohrer. 

While the age-related personality differences would disappear with age, they may be “kept alive” within the family context. 

“Think of the firstborn who, as a child, gets more responsibility due to her age, and then later keeps being the responsible sibling when the family gets together for Christmas (but not necessarily in other contexts, such as at work or with their peers),” explains Rohrer. 

Psychological Impact on Youngest Children

Louis J. Kraus, MD, director of child and adolescent psychiatry at Rush University, says how kids are raised and their genetics both have psychological effects, “but as time goes on and as they grow, the effects are somewhat less obvious and you have to be careful formally labeling anybody,” he says. 

Relationships between the youngest child and their older siblings may be influenced by family dynamics. For instance, Kraus says it is not uncommon that the oldest child is more helpful with their younger siblings and that the youngest child is more animated and attention-seeking. 

“With that, there is a question of whether there is a more immature quality with them that they tend to infantilize a bit more, and are a little closer to mom than their older sibling counterparts,” Kraus says. “[If] you grab an average family with three kids or more, they would describe this dynamic probably more often than not, even if there is no definitive research to support it.” 

Relationship with Siblings and Family Dynamics

Parenting may have something to do with the dynamics, he adds, noting that when parents have their first child, they typically are overprotective. “Everything gets sanitized, they do everything by the book, and by their second child, they’re a little easier going,” he says. “If the pacifier falls on the floor, maybe they’ll wipe it off and give it back to the child. It’s no longer a big deal.” 

In families with more than two kids, the youngest child may receive somewhat less attention in the early years of life because they have to “share” it with older siblings. “At the same time, they are likely to experience a period later when the older siblings have moved out, and they get ‘exclusive access’ to parents,” says Rohrer. 

She adds that the middleborn children are theoretically the ones who have the largest disadvantage in parental attention. “Maybe attention in younger years matters more and so youngest children do get a worse deal, but in any case, we don’t have much evidence that it affects their personality in the long run,” she says. 

Coping Strategies for Youngest Children and Parents

Parenting or being the youngest child can come with challenges and advantages. However, acknowledging that birth order may affect your child or you is a great way to embrace it. 

Experts share ways to navigate the youngest child syndrome for parents and those living life as the youngest child. 

For Parents

As you raise your youngest child, Kraus says, think about what not to do with all your children:

• Don’t give your oldest child too much responsibility
• Don’t ignore your middle child
• Don’t infantilize your youngest child

“What you do, is you do the best you can as parents. You try to love your kids equally, you try and support them, and you realize they’re going to have different personalities and are going to be different kids,” he says. 

Recognizing that you can’t make kids fall into a line and be exactly as you expect is key, Kraus stresses. “Kids have their own genetics and they react to environmental stressors and support differently. You might see similar characteristics with your kids and you might not,” he notes. 

“Parents may read one book or another book about how it should be and they might even have certain expectations, but at the end of the day, kids are surprise packages. You don’t know what you’re going to get for sure and the best you can do as a parent is to love and support your kids as equally as you can,” Kraus says. 

For Youngest Children

If you are currently a minor and struggling with being the youngest child, talk with your parents about what’s bothering you and ask if they can help you find a therapist to talk to. If you are uncomfortable talking to your parents, ask a teacher, coach, or another trusted adult to help you. 

Rohrer stresses that the differences between each family dwarf any systematic effects of birth order position. “This does not mean that siblings do not matter for personality; it is quite possible that they do matter—but in highly individual ways that do not result in something like a ‘typical youngest child’ pattern,” she says. 

With this notion in mind, try to embrace your unique qualities and strengths as an individual despite your birth order. Consider ways your qualities as a youngest child can help you feel empowered. For inspiration, consider many celebrities and successful people who are the youngest children, including Zooey Deschanel, Jake Gyllenhaal, Hilary Duff, and Harry Styles.

If you need help processing your family dynamics and place as the youngest child, reach out to a mental health professional for guidance.