To continue my comments. Family in an anarchistic way would run contrary to the social order, but not necessarily because the family should be shaped as anti-social-order. It just would happen to, as most families have values that hold themselves in a greater or lesser extent in conflict with the values of the capitalist economic system. Family for the capitalist, as the subject of capitalism, is often as much of an institution as a business or university is. Those not the subject of capitalism, the subjected, gain here and there in how the definition of family and the values of family are defined, but also lose much.
The materialism of the life we currently live in has to support defined beginnings and ends to marriage as it does to death. There are large benefits to remaining outside a family structure in capitalism. A professional, as a skilled servant of capitalism, tends to be rewarded more for allowing their occupation to take up most of their time and thus become their life.
In a way, "occupation" makes sense in the double entendre. Capitalism for the professional has occupied their life, has invaded it and taken residence. Even for the less "professional" professional, there is more focus on their job than the traditional working class and often the capitalist. The rewards for the professional are large for removing family considerations or allowing them to become secondary, often to the point of neglect.
The unsklled working class (i.e. precariat), as subjected to capitalism, is also subjected to the greater social order. It is not just the economic system of the capitalist, but the government and civil society that has the working class under control. Religion, unions, addiction treatments, prison, schooling, "therapeutic" meetings, medical assistance, social security, child welfare services, child support, homeless shelters, section 8 housing, etc. Often the working life of the unskilled working class is an escape from the problems of society rather than considered a problem. Family has often become an ugly thing to them, plagued with issues, constant fights within the family and attempts to hold the family together against government and civil society's interventions. Religion steps in and sometimes there is deep spiritual agreement, but other times, religion is indoctrination, teaching the individual to accept the way things are.
So an anarchistic family may challenge all of this, but may very well also face the same issues of control that all families suffer from. It isn't just because the social norms are attempts for an egalitarian life, the attempts to remove family hierarchy and patriarchal attitudes. It isn't because religion is questioned and a spirituality is found that doesn't impose itself on the individual and family. These things might be challenged now, but there is a relationship to society that can't be broken. We can avoid and escape, attempt to form safe spaces, but this dodging is not freedom, it is an expression of fear. The family is still defined by its legal relationships, its relationships to the social norms of society, the dominant cultures, the dominant religions.
It makes sense to create our own families, as anarchists. It makes sense to find and share values with others that are similar to us in an attempt to form communities with each other. But it also makes sense for the anarchist to acknowledge that we can not escape or hide from society and that deviation from the dominant cultures that define our present order will see our lives intruded upon. Just as we aim to form affinity groups of attack, our families may need the same kind of considerations.