Theories arguing the mother's role cannot be replaced by the father may lead to stigmatization of single-father or two-father families, with economic implications
Found that playing with the father is more exciting and pleasurable for infants. This supports the view of the father as a playmate.
Hardy(1999) - poor primary caregiver
Found that fathers are less able to detect low levels of distress in infants, so they may be unsuitable for the role of primary caregiver.
Lamb(1987) - good mood
Found that infants seek the father when in a positive emotional state, so they want stimulation, not comfort. Also found that male main caregivers develop sensitive responsiveness quickly.
Belsky et al. (2009) - partner affect
Found that father-infant attachments were more secure when marital intimacy was higher.