Siobhan was first diagnosed with breast cancer in May 2019 and had surgery, and also was treated with chemotherapy, radiotherapy and hormone therapy. In October 2019 she was diagnosed with metastatic breast cancer. A scientist by profession, Siobhan has worked in medicines research and development, including in clinical trials and programme management. Indeed, she worked at Cancer Trials Ireland where she helped to set up its quality and training division (2003-2007). Siobhan sits on the Breast DSSG.