Family life issues.

In his later novels Heinlein explores the issues of family life for a competent, economically productive, female who has the normal female drive for reproduction, nurturing and child care. This may be where Heinlein parts company with conventional feminists who seem to think that babies are incompatible with full participation in life as an economically productive adult. His solutions are generally forms of group marriage, with the men selected, it seems for their willingness to take the "pee watch" that is, to accept their responsibility for the care and nurturing of the children. In Heinlein novels preservation and enhancement of the species through reproduction by the most competent, in Heinlein's case usually females, is a given.