As parents across Nebraska know, children are similar to their parents in ways many are unable to predict. A new study believes that children who have divorced parents may end up similarly divorced not because they are repeating their parents’ behavior but because of genetics.

As Science Daily reports, a study conducted by researchers at Virginia Commonwealth University and at Sweden’s Lund University found that genetics were a strong predictor of divorce tracing Sweden’s national registry to find the marital patterns of adults who were adopted as children. Children who were not raised by their biological parents were still more likely to resemble the marriage pattern of their genetic parents and siblings than the parents who raised them. Researchers believe this could be due to relationship traits that have shown they can be passed on genetically, such as impulsiveness or being neurotic. These traits are also linked to higher rates of divorce.

As Health.com notes, the researchers studied 20,000 Swedes who were adopted in their youth and were surprised to find that it was not the marital histories of their adoptive parents that were replicated most often. The commonly-held assumption was that children of divorce were more likely to divorce because they were imitating the behavior they saw in their own parents’ relationship. And researchers did find that those environmental factors made an impact. They also studied 80,000 adults who were raised by their biological mother and a step-father and found that while there was a correlation with the biological father’s divorce history, a stronger indicator of divorce was whether or not the mother remained married to the step-father.