In this article, I challenge the widespread presumption that a child should have exactly two parents. I consider the pros and cons of various numbers of parents for the people most directly affected – the children themselves and their parents. The number of parents, as well as the ratio of parents to children, may have an impact on what resources are available, what relationships can develop between parents and children, what level of conflict can be expected in the family, as (...) well as the costs involved in parenting and the experience of parenting a child. Indirectly, there is also an effect on who will have the opportunity to be a parent, as well as on wider social issues that I mention but do not discuss. Having considered all these factors, I conclude that there is some reason to believe that three or more parents is usually better than one or two, especially if children are to have siblings, which is typically beneficial. However, these reasons are not strong enough to support a general presumption in favor of any particular number. We should therefore jettison the two‐parent presumption and make different numbers of parents more socially accepted as well as legally possible. (shrink)