There Might Actually Be Some Science Behind Eldest Daughter Syndrome

She often struggled with feeling like her responsibilities and those of her mother were becoming indistinguishable.

When I was nearly 11 years old and my youngest brother was born, I was instantly overwhelmed with a strong sense of responsibility for his well-being. I would often sit beside his crib and watch him sleep, just to ensure his safety.

"I had become the one primarily responsible for taking care of my family by that point in my life," she explained.

The social media platform commonly referred to as "Twitter."

Though "eldest daughter syndrome" is a colloquially used term without a formal definition in the DSM, a recent study implies there may be underlying psychological factors at play that make the idea more than just a myth.

This allowed them to help their mother take care of younger siblings.

Research has discovered a notable connection between early physical signs of puberty in older sisters and their mothers experiencing high stress before pregnancy.

What's going on during this time period. Changes in skin, such as acne, and body hair occur, but so do changes in brain development. It's thought that the adrenal glands' involvement in puberty helps to shape both social and cognitive development, really, physical changes on the surface are linked to emotional maturity.

During difficult times and when the mother is feeling extremely stressed during pregnancy, it is generally in the best interest of the mother and her daughter that the daughter develops social maturity at an accelerated pace, according to remarks by Jennifer Hahn-Holbrook, an expert in psychology at the University of California, Merced.

She said providing the 'helper-at-the-nest' trait earlier allows mothers to better care for their babies, especially when resources are scarce.

Notably, adrenal puberty doesn't include breast growth or the beginning of menstruation for girls (or testicular growth in boys). The research suggests that girls develop enough mentally to care for their younger siblings, even though they physically aren't ready to have their own children, which means they shouldn't be taken away from their responsibilities to their older daughters.

The researchers could not replicate this outcome in children who were not born first, neither boys nor girls.

One possible reason we didn't see this effect in first-born male children may be because boys tend to help less with childcare, leaving mothers with less reason to accelerate their son's social development.

She also mentioned that previous studies indicate female puberty timing is more easily influenced by early life experiences than that of males.

Researchers had been studying the effects of Prenatal Psychoneuroendocrinology - that's a mouthful! - for a very long time: For 15 years, they tracked families from pregnancy through the babies' teenage years.

Researchers chose mothers-to-be from two Southern California prenatal care offices, visiting them when they were approximately a month into their pregnancy. The average age of the women was 30 years, and they were carrying a single baby, not twins.

Most of the women in the study were pregnant for the first time. They were healthy females who had not used tobacco, steroid medications, alcohol, or other recreational drugs during pregnancy. All the women were at least 18 years old.

During pregnancy, women's levels of stress, depression, and anxiety were measured at five distinct points, with the data compiled collectively. The assessment of depression asked women how true they found statements like, "I felt lonely," whilst the anxiety survey inquired about how frequently they experienced symptoms such as "feeling jumpy."

Of the children born to these mothers, nearly two out of every five were female, while slightly more than two out of every five were male.

As the children grew older, their physical changes during puberty were closely monitored, pinpointing characteristics associated with growth spurts, body hair, facial hair, skin changes, breast development in females, and the start of menstruation, as well as voice changes in males.

The study also considered early childhood hardships as potential factors influencing onset of puberty, such as parental loss, parental separation before five years old, father absence, and economic instability between ages seven and nine.

Given these factors, the eldest daughters among them were significantly influenced by their mothers' high levels of prenatal stress during pregnancy.

Wolfe's personal experience aligning with the study's results resonates with her, as she had a maternal figure to her siblings in her own childhood.

Wolfe remarked, "I'm not surprised by the study's findings." However, his personal experience diverged slightly, as he underwent physical puberty at age 12 while likely developing cognitively earlier than his peers.

A particularly intriguing field of research that investigates how prenatal stress and other emotional and environmental influences on pregnant women can have lasting effects on their children.

"This is a one-of-a-kind discovery that's interesting to consider when looking at evolution," says UCLA anthropologist Molly Fox, who is a co-author of the study.

In a recent conversation, Fox explored the intricacies of how fetal programming occurs.

One intriguing idea is that even before we're born, we pick up on subtle hints about the kind of world we're entering, and our bodies adapt to that by shaping our physical and possibly even mental growth in ways that prepare us for what we expect to face.

Fox and her co-authors are thrilled to finally make their research available to the public, especially after years of watching the families they studied up close. The coincidence of publishing their findings as the conversation about eldest daughters gained momentum is an added bonus, particularly for Fox, who is herself a twin and second in line after her co-eldest sibling.

"I think being an older sibling in our family is really special because of the extra time I get to spend with my mom and the opportunity to take care of my little brothers and sisters," she said.

Talking like a classic, responsible, and caring older sister.