Children fail to benefit from parental human capital without strong bonds. [causal]
Even if adults are physically present, there is a lack of social capital in the family if there are not strong relations between children and parents. The lack of strong relations can result from the child's embeddedness in a youth community, from the parents' embeddedness in relationships with other adults that do not cross generations, or from other sources. Whatever the source, it means that whatever human capital exists in the parents, the child does not profit from it because the social capital is missing.
Builds on: "Parental human capital requires family social capital to benefit children."
Coleman, SocialCapitalCreation-1988, loc. 155