Family forms such as open adoption, lesbian, and surrogacy produce at least two mothers to the same child(ren). Similarly, reconstituted families following parents’ separation and re-partnering often produce multiple parents, and may include a step and a birth mother. Diverse family forms where maternal subjectivity is dispersed between two or more women are becoming ubiquitous in New Zealand and other Anglo-American countries. As a result of the changes, defining parenthood has become increasingly complex. When two women are positioned as ‘mother’ through the same unitary signifier it is problematic especially when they are present together. The women are often understood by others to be in competition with each other and thus create anxiety in those around them. This inquiry, drawing on literature, cinematic representations, anecdote, and popular media, has used psychoanalytic resources to explore the social anxiety that dual mothers elicit. The inquiry concludes that the cultural imperative in Anglo-American societies for an individualised ‘identity’, embodied in the nomenclature of ‘mother’, bars recognition for one of the mothers. The failure to recognize them both as ‘mother’ means they must construct themselves and their co-relationship counter discursively. The social anxiety that is produced as a consequence of troubled identification may be defended against by splitting. The mothers are then positioned as ‘good’ and ‘bad’ through existing discourses that either reify or demonise mothers. The inquiry recommends the development of both structural and individual interventions and proposes directions for further research.