Quick look
Parent‑teen friction may seem fleeting, but new Iowa State research shows those tense adolescent moments can echo through a family for decades. A multigenerational study finds that harsh parenting in adolescence can weaken bonds not only between parents and adult children, but between grandparents and grandchildren as well.
AMES, Iowa - Parent-teen tension is often treated as a phase - something to be endured, then forgotten. A common by-product of growing up.
But does it really get left behind?
A new study from Iowa State University reports parent‑teen conflict can reverberate for decades and even influence how connected families feel generations later.
The study's findings draw from the university's longstanding Family Transitions Project, one of the nation's most extensive longitudinal studies of family life. Since 1989, researchers have followed more than 550 individuals and their families in rural Iowa, a cohort that began with early adolescents and their parents, and has now expanded into three generations.
"The original teens have been followed into adulthood, while their parents have been followed into grandparenthood," said Tricia Neppl, professor of human development and family studies at Iowa State. "This multigenerational reach is what allows us to trace how an exchange in a living room in 1991 can show up decades later in how emotionally close a grandparent feels to a grandchild born in 2020."
Over that span, the researchers saw a clear pattern emerge.
"Harsh parenting during the adolescent years can shape family relationships well into the next generation," said Neppl, who also serves as principal investigator and site director for the Family Transitions Project.
"What happens in adolescence doesn't stay there."
Neppl said this pattern holds for both mothers and fathers, noting "early conflict predicts later distance - first between parents and their adult children, and then between grandparents and grandchildren."
The new study, published in Family Relations, was co-authored by Neppl and fellow researchers Jannatul Ferdous Zinia, a current Ph.D. student in human development and family studies at Iowa State, and Olivia N. Diggs, a graduate of Iowa State's Ph.D. program in human development and family studies.
How the researchers measured 'harsh parenting'
Neppl said the study's strength comes from its direct observation of families, offering "a methodological advantage that sets the project apart from most long‑term research, which often relies on surveys or retrospective reports."
In the study, 16-year-olds and their parents participated in videotaped discussions about everyday topics - school, chores, family rules - while independent observers coded parental behavior on a nine‑point scale, noting signs of:
- Hostility defined by researchers as annoyed, critical or disapproving behavior;
- Angry coercion defined as attempts to control the teen in a hostile manner;
- Antisocial behavior defined as rebellious or indifferent responses.
More than a decade later, those same teens - now adults in their late 20s - rated how satisfied and happy they felt in their relationships with their parents.
"We consistently found that higher levels of harsh parenting during adolescence predicted lower levels of closeness and satisfaction in adulthood," Neppl said.
And the effects didn't stop there.
When the next generation arrived
By the time those adults became parents themselves, the original parents - now grandparents - reported feeling less appreciated, less understood and less emotionally close to their grandchildren. The early strain between parent and teen appeared to limit how warmly the next generation connected.
Neppl said harsh parenting in adolescence set off a chain reaction: Strained parent‑child relationships in adulthood made it harder for grandparents to build strong ties with grandchildren. This multigenerational pattern underscores how relationship dynamics can travel through families, shaping bonds long after the original conflict has faded.
"These are everyday moments - the tone, the response, the way frustration is expressed," she said. "Over time, these moments accumulate and can influence how families relate decades later."
Why these findings matter now
The study's results arrive at a moment when grandparents play an increasingly central role in American family life. In many households, grandparents are essential to daily routines, providing childcare, emotional stability and mentorship.
But Neppl said those roles depend on strong ties with adult children and grandchildren, ties that may be shaped decades earlier.
"Our findings highlight the importance of early intervention and support for families navigating adolescence," Neppl said. "Families can change, but the earlier we address harsh parenting, the more likely we are to preserve these multigenerational connections."
Neppl said the study also adds to a growing body of research showing that parenting practices in adolescence can have long‑term consequences, not only for adolescent development but for the structure and strength of family relationships across generations.
The broader implications
Overall, the study's findings point to a key takeaway, Neppl said: the tone parents set during the teen years matters, not just for the immediate relationship but for the family's future architecture.
She noted that programs that help parents manage conflict, regulate frustration and communicate more effectively could have benefits that extend far beyond adolescence.
"Supporting parents during the adolescent years isn't just about improving the parent‑child relationship in the moment," she said. "It's about strengthening families for generations."
