Three studies of 1,694 parents found fathers of daughters reported greater commitment, attachment and trust toward their partners than fathers of sons. Mothers of daughters also reported more support from them.
Fathers of daughters reported stronger attachment, commitment and trust toward their child’s mother than fathers of sons did, according to three studies of 1,694 parents. Mothers of daughters also said they received more romantic support from their partners shortly after the birth. A third study followed couples from pregnancy and found no difference between the two groups of expectant fathers before the baby arrived. The researchers say the effect is real but small, and they are careful about what it does and does not mean.
The idea comes from paternal investment theory, which holds that a father shows his daughter what to expect from men in relationships. Earlier studies linked father absence to earlier sexual activity and earlier puberty in daughters. Researchers at Rutgers Business School asked the reverse question. “No prior study had looked at the reverse, the impact having a daughter has on a man,” said Kristina Durante, one of the authors.
What the three studies found
The first study surveyed 184 parents of a single child under 18, 101 fathers and 83 mothers. Fathers of daughters reported stronger attachment to the child’s mother than fathers of sons, averaging 8.04 on a 9-point scale versus 7.37. They also reported higher commitment, satisfaction and trust. Mothers’ own reports did not differ by the child’s sex.
The second study used data on 587 couples from the Fragile Families and Child Wellbeing Study, tracked from the child’s birth to age nine. Mothers of daughters reported receiving more partner-directed support, such as affection and fairness, shortly after the birth. There were no differences in general parenting or co-parenting, and fathers’ views of the mothers’ supportiveness did not vary with the child’s sex. The gap narrowed as the children grew older.
The third study followed 168 first-time parent couples from the third trimester through the child’s second year. Before the birth, expectant fathers of sons and daughters did not differ. After the birth, fathers of daughters reported greater relationship satisfaction, provided more support and showed lower attachment anxiety. Satisfaction with childcare did not change with the child’s sex.
How big the effect is
Durante described the effects as small to medium, about half a standard deviation on measures such as commitment and relationship satisfaction. “The effect isn’t large enough to predict any single father’s behavior,” she said. She also cautioned against reading it as a verdict on fathers: “It’s not that dads love daughters more than sons. It’s not that fathers of sons are bad partners.”
What the studies cannot say
Durante noted that the effect was found in the United States and may not translate to non-Western populations. All the couples were heterosexual, so it is unknown whether similar dynamics appear in other partnerships. Following couples from pregnancy helps rule out that men with daughters simply differed beforehand, but it cannot explain why the shift happens.
The authors point to evolutionary theory and the drop in testosterone that comes with fatherhood as possible explanations. Neither has been tested here. The first and third studies are also small.
Source
Duarte K, Durante KM, Gassen J, Reed A, Rholes S, Simpson JA. “Daughters promote pair-bonding in fathers in modern Western cultures.” Personality and Individual Differences, 2026, article 113901.
DOI: 10.1016/j.paid.2026.113901
