Objectives This study will explore how help is constructed during and following radiotherapy for patients with cancer. Methods Grounded theory methods were used in the study to explore the way in which family members and friends constructed a role for themselves in relation to patients receiving radiotherapy. A total of 22 helpers were interviewed. Patients were being treated for a range of cancers including breast, prostate, colorectal, and head and neck. Results Respondents in this study consistently defined themselves as “helpers” rather than “carers.” While radiotherapy as a treatment modality was mostly seen as noninvasive, the cancer diagnosis cast a long shadow over the lives of helpers and patients creating a separation in longstanding relationships. Helpers experienced this separation as “otherness.” Help became an important vehicle for bridging this separation. Individuals developed different ways of knowing about the patient as the basis for providing help. Two different types of help were identified in this study: the behind the scenes, largely invisible work that helpers undertook to help the patient without their knowledge and the explicit visible help that was much more commonly negotiated and discussed between helpers and patients. Conclusions The study provides the basis for a greater understanding on the part of professionals into the impact of diagnosis and radiotherapy treatment on family and friends. In doing so, the study identifies opportunities for the experience of helpers to be recognised and supported by professionals.