New York: Adolescent girls with the presence of their boomerang fathers -- who enter and exit their children's lives -- are less likely to experience depression even after undergoing stressful experiences like family instability, absence of biological father or the presence of stepfather, says a study. The findings showed that adolescent girls exposed to boomerang fathers had lower depressive symptoms at 18 years of age than those exposed to instable non-boomerang fathers. "Boomerang fathering served as a protective factor for female adolescent depression compared to female adolescents who experienced instability, but not boomerang fathers," said lead researcher Daphne Hernandez, Assistant Professor at University of Houston in Texas, US. "Even though the family has gone through some really bad times, having the dad come back home has proven to be positive," said Cassandra Dorius, Assistant Professor at Iowa State University in the US. However, boomerang fathering was not significantly related to depression in adolescent boys. Biological parents who boomerang are more likely to be single at the time of their child's birth, which is "a gateway for which boomeranging exists" since there is no legal or residential commitment, the researchers said. "Although the relationship between the biological father and mother may be complex, there is a commitment to the child by the boomerang father that creates a bond between father and child," Hernandez explained. Additionally, most households with boomeranging fathers did not experience a step-parent or non-biological father presence. "Familiarity of a biological father who enters and exits the house may deter non-biological partners from entering their children's lives, lowering the activation of the hormone that causes stress and depression," Hernandez noted. For the study, the team examined responses from nearly 4,000 youth who were 18 years old by the year 2010 and more than 3,300 mothers. The family instability is more fluid and complex than previously thought, indicating greater family support during such times. It may assist in creating positive mental health, the researchers concluded in the work appearing in the Journal of Marriage and Family.