We know that birth order can have a big effect on a persons experience growing up within their family. Its not unusual for people to assume that a youngest child will be babied and lavished with attention, a middle child forgotten amid the fray or a firstborn bossing around their siblings.

At the intersection between the plight of the firstborn and our gendered expectations of who should take on caregiving duties lies eldest daughter syndrome , a non-clinical name for the way these pressures tend to shape the lives and personalities of oldest daughters.

Lisette Schuitemaker, author of The Eldest Daughter Effect: How Firstborn Women Harness Their Strengths , told HuffPost in a previous interview: Our particular life path makes us into responsible, dutiful, hands-on, thoughtful and caring women.

Having been trained to take the lead from a young age, Schuitemaker continued, its not surprising that oldest daughters are overrepresented in positions of leadership. Hillary Clinton, Oprah Winfrey and Beyonc are some of the oldest daughters Schuitemaker mentions in her book.

There are other effects of being the eldest daughter, however, that are less positive. Girls may be unfairly burdened with caregiving responsibilities because of their gender, becoming parentified , or feeling responsible at an early age for duties that would usually fall to a parent.

A new study has identified another way firstborn and only children may be affected by birth order and this doesnt apply only to girls. A team at Epic Research analyzed the medical records of over 180,000 children and found that firstborn children with siblings were 48% more likely to have anxiety and 35% more likely to have depression by the age of 8 when compared with children born second or later in their families.

The finding held for only children as well, who were found 42% more likely to have anxiety and 38% more likely to have depression by age 8 when compared with children born second or later. Researchers controlled for other factors, including the childs and the mothers mental health histories.

While the study does not examine why firstborns and only children are more likely to receive these diagnoses, it does identify birth order as a potential marker of risk (among many) for anxiety and depression. The finding adds to our understanding of kids risk factors, Caleb Cox, head of research and data science at Epic Research, told HuffPost.

Anxiety and depression dont have a single cause, so understanding what factors are likely to impact a child can help both parents and clinicians to make sure that they are helping the child with their specific needs, Cox continued. He noted that there are plenty of second- or later-born children who struggle with anxiety and depression as well, so its important for parents to make sure their kids are getting the help that they need, regardless of the childs birth order.