Joshua Goodman, an associate professor of education and economics at Boston University, found equally impressive effects at the university level. Goodman saw a dataset of students who were correct to the margin of cutoff points established for entry into something called “target colleges.” Candidates are essentially equivalent, their scores vary by 10 points or less, and are a function where one student simply makes the other question right. However, on average, those just above the threshold achieved admittance, and those just below. Goodman found that younger siblings of recognized people were much more likely to go to a similarly selective university than those older siblings missed out on just a few points. The younger brothers who have reached an elective university may have raised their expectations. They could see the path forward. They could benefit from what their older brothers did.
Michelle Obama's university experience can be seen as a reflection of Goodman's findings, but he applied decades before taking on his research. Obama's parents raised her in a working-class neighborhood on the south side of Chicago. Her older brother Craig was a strong student, but the Ivy League school was not on her parents' radar. However, Craig also had the advantage of becoming a star athlete. That's why he was hired to play basketball at Princeton University. As Obama writes in her book Beging, seeing where her brother ended expanded her own sense of potential. “No one in my family has had any first-hand experiences at university, so there was little discussion or exploration anyway,” Obama wrote about his visit to his university siblings. “As always, I thought, I wanted whatever Craig liked, and whatever he could achieve, I could do that too. And with that, Princeton became my best choice in school,” the guidance counselor told her, she “is not Princeton's material.” That didn't discourage Obama. She writes her own faith. However, it is very likely that she knew her talent well enough to assess her talent. She knew that if he was Princeton material, she would certainly have been.
The findings of Zang and Goodman suggest that effective interventions in one child from a low-income family could also have a positive knock-on effect on siblings. In other words, interventions may have more impact than previously achieved. It can improve the experience of older siblings and have ripple effects that change the trajectory of the whole family.
Zang's study found that almost a third of sibling academic similarities could be attributed to spillover effects (as opposed to shared environments and overlapping genetics). However, ripple effects can also function negatively, especially in underprivileged families. Children who grow up in underprivileged homes are more likely to suffer academically due to various confusion. But the child scholar will further suffer further from the traumatic revelations that have hurt his brother's success in school, Zan theorizes. Because test scores are reliable predictors of income later in life, the effects of siblings in these families can lead to lower lifetime revenues.
Both Zang and Goodman find that the spillover effect is strongest in underprivileged families, highlighting the need for researchers to acknowledge that sibling influences differ in different functions in the line of class. For example, a study published in the Frontier of Psychology in 2022 complicated a well-replicaed finding that the oldest siblings are the most academically highly regarded in the family. The oldest siblings of high-risk families and families whose parents are not native English speakers actually do not score a higher score on cognitive tests if they are more school-ready at 2 years old. These families have years of experience in dialogue with older siblings due to the pervasiveness of older siblings.
