The paternal bond is typically the relationship between a father and his child. In the U.S., legal paternity is presumed for the husband of the mother unless a separate action is taken; an unmarried man may establish paternity by signing a voluntary recognition of paternity or by taking court action. Paternity may also be established between a man and a younger person, commonly in adoption, without the two being related to each other.
The father of a child can develop the bond during the pregnancy of his partner, feeling attachment to the developing child. Research indicates that this may have some biological basis. Statistics show that fathers' levels of testosterone tend to decline several months before the birth of the child (due, perhaps, to an inverse pheromonal chemical produced by the mother during pregnancy). Since high testosterone levels seem to encourage more aggressive behaviour, low levels may enhance the ability to develop a new relationship bond (for example, with the child).
Fathers find many ways to bond with their children, such as soothing, consoling, feeding (expressed breast milk, infant formula or baby food), changing diapers, bathing, dressing, playing, and cuddling. Carrying the infant in a sling or backpack or pushing them in a baby transport can build the bond, as can participating in the baby's bedtime routine.
- Early Childhood Longitudinal Study 2006. "Measuring Father Involvement in Young Children's Lives." National Center for Education Statistics. Fathers of U.S. children born in 2001.
- U.S. Department of Health and Human Services, Administration for Children and Families, Office of Child Support Enforcement. "Handbook on Child Support Enforcement." (Washington, DC: Author) 
- Linda F. Palmer. "Bonding Matters: The Chemistry of Attachment." Attachment Parenting International News: Vol. 5, No. 2, 2002.
- Douglas Carlton Abrams, "The Making of a Modern Dad." Psychology Today, Mar/Apr 2002.