Dominant Western discourses of motherhood have depicted disabled women as incapable of being mothers. In contrast to these representations, recent literature in disability studies has argued that disabled women can provide maternal care and should therefore retain custody over their children. This literature is commendable, but its emphasis on custodial rights excludes from the category of “mother” those disabled women who cannot maintain child custody. In this article, I challenge this exclusion via an account of my experience with my two mothers: my biological mother, who relinquished custody over me because of her inability to provide care, and my maternal grandmother, who raised me as her child. Theorizing this account, I argue that disability studies must adopt a conception of motherhood that recognizes both alternative kinship structures and mothers whose disabilities preclude them from fulfilling normative conceptions of maternal care. I develop such a conception by synthesizing Judith Butler's theorization of queer kinship with Donald Winnicott's rethinking of the maternal subject. I conclude by drawing on this flexible conception of motherhood to argue that my disabled mother's relinquishing of custody over me to her own mother was the very gesture in which she accepted and adopted a maternal role.