This study explored how women with a diagnosis of cancer (lymphoma) deal with moral concerns related to their responsibility as parents. Ten women with cancer and who had children living at home were interviewed. The interviews were analysed according to the constant comparative method used in grounded theory. In order to provide a focus for the analysis, the ethics of care and the concept of mothering were used as sensitizing concepts. The core concept ‘experience of dealing with moral responsibility of being a parent with cancer by redefining oneself as a mother’ was identified. The processes involved were: interrupted mothering; facing the life-threatening illness and children’s reactions; striving to be a good mother; attempting to deal with moral responsibility; and coming to terms with being a mother.