This contribution builds on the Design Framework for System-of-Systems Resilience to investigate the potential of a new systems resilience measuring approach inspired by the Frailty Index. To explore this research direction, we provide a brief overview of the evolution of the notion of resilience, offer a characterisation of systems resilience as an opposite of systems frailty, and perform a rapid review to identify and inspect existing multi-domain indices of community resilience. Finally, we suggest piloting the proposed system-of-systems resilience index in the Fens in the United Kingdom.