Some researchers attempting to answer questions about the role of fathers are actually more concerned with understanding fathers as secondary attachment figures rather than primary attachment figures
Longitudinal studies have suggested that fathers as secondary attachment figures have an important and distinct role in their children's development, involving play and stimulation
If fathers have a distinctive and important role, we would expect children in single-mother and lesbian-parent families to develop differently than children in heterosexual families, but research has not consistently shown this
Preconceptions about how fathers do or should behave can be created by stereotypical accounts and images of parenting roles and behavior, which may cause observer bias in the studies