Marxist

Marxists are conflict theorists, they have a critical view on the family.
The family provides important funcitons for capitalism

Families arose because of private property! Fathers needed to be sure who their offspring where in order to pass down their property to the right children.
Need for monogamy arose (one man married to one woman).
Family now serves the interests of the economy, women are subjected to unequal power in relations in the home.

The family serves capitalism!
Offers emotional security from the oppressive world of work, allowing such oppression to continue. In reality it offers emotional warmth encouraging its members to continue to live another day under harsh realities of capitalism.

Family serves functions for an ideological state apparatus by socialising both pro-capitalist ideology and own familiar ideology in order to maintain such family patterns overtime.
For example:
Family socialises its members into accepting gender roles, its natural for men and women to get married and engage in seperate roles in the home an attitude which has been passed down from generation to generation.