A thoraco-abdominal branch graft prosthesis includes a lumen main graft component that defines a lumen and at least one main graft wall fenestration. At least one tunnel graft component of the branch graft prosthesis defines at least one tunnel graft fenestration. The tunnel graft component is within the main graft lumen defined by the luminal main graft component. A luminal wall of the tunnel graft component is fixed to the luminal wall of the main graft component. The fenestration of the tunnel graft wall is aligned with the fenestration of the main graft wall. The thoraco-abdominal branch graft prosthesis can be implanted in a patient at a site of a thoraco-abdominal aneurysm.
