Murdered MPâs sister Kim Leadbeater has told friends she could contest crucial byelection for party Kim Leadbeater is a campaigner and an ambassador for the Jo Cox Foundation, dedicated to continuing her sisterâs legacy. Photograph: Gary Calton/The Observer Kim Leadbeater is a campaigner and an ambassador for the Jo Cox Foundation, dedicated to continuing her sisterâs legacy. Photograph: Gary Calton/The Observer Wed 12 May 2021 01.00 EDT The sister of the murdered MP Jo Cox is considering standing for Labour in the Batley and Spen byelection. Labour is facing a huge test to c...