Referencing a paper that more than a decade ago unleashed fierce ideological debate over whether children need both a mother and a father to develop properly (Silverstein & Auerbach, 1999), Biblarz and Stacey (2010) attempt to reignite the debate by posing the question How does the gender of parents matter? Finding studies that specifically addressed this issue was difficult, the authors noted, because most do not or cannot tease out the effects of the parent's gender from the number of parents in the household, sexual identity, marital status, or biogenetic relationship to children. To separate the effects of gender from these other confounding variables, the authors selected two bodies of research - studies that compared differences between male and female single biological parents and studies that compared differences between planned lesbian coparent families with heterosexual (married-parent) families. These studies were then reviewed for their evidence as to whether there were parenting abilities specific to men and women and whether child development is harmed by fatherless or motherless parenting. According to Biblarz and Stacey, comparisons of parenting and child outcomes between male and female parents in a variety of family structure configurations generally revealed no significant differences, and where differences did occur, women, particularly lesbian women, appeared to parent better than men, particularly heterosexual men. It is important to say at the outset that the task that Biblarz and Stacey (2010) have undertaken is daunting, not just because it is controversial but also because of the near intractability of sorting out the unique contributions of these five variables. I also think that there is sufficient empirical evidence to suggest that children are as likely to thrive in heterosexual parent households as they are in same-sex parent households. Having said that, what makes me uneasy about this paper is that its narrow focus on a child's social address (i.e., family type) necessarily draws attention away from the things that matter more for child wellbeing and development. Many of the articles cited by Biblarz and Stacy, including the work by Silverstein and Auerbach (1999), qualified their analyses by placing observed differences in family type in context with other factors that influence child outcomes. Biblarz and Stacey, however, provided no such context and thus failed to see how these insights might have tempered their own findings. Importantly, their attempt to interpret point-in-time comparisons of parenting and child outcomes across different family types simply repeats the error committed by those on the other side of this ideological argument. The error, of course, is that a crosssectional examination of child and parenting outcomes across different family structures tells us something meaningful about what children need to succeed in life. Moreover, despite acknowledging that they were unable to find any studies that completely separate the effects of gender from the confounding effects of marital status, number of parents in the household, sexual identity, and biogenetic relationship to children, their own language throughout the paper reflects a tendency to conflate these key variables. More than a simple error in language, I argue that these problems speak to the inherent complexities, but also the increasing importance, of being able to make distinctions among these key variables in order to advance our understanding of how families matter. Placing Social Address Variables in Context Inasmuch as researchers are interested in understanding how family and child wellbeing are uniquely influenced by parental gender, sexual identity, marital status, biogenetic relationship to children, and number of parents in the household, there is general consensus that these variables do not in and of themselves tell us anything about why differences exist. Such variables simply locate families in terms of their setting or their social address, where observed differences are then explained as attributes of the setting (Bronfenbrenner, 1979, p. …