Canadian Israeli activist Vivian Silver dedicated her life to peace. When she was killed in the Oct. 7 attacks, her sons faced an impossible question: Is peace still worth fighting for? Read more:Vivian Silver grew up in Winnipeg, Canada, and moved to Israel in 1974 to start a new kibbutz and devote her life to peace. She arranged a solidarity bike ride on both sides of the Gaza border fence. Her friends from Gaza called her on Jewish holidays. Her politics had been unwavering.But then, Silver was missing after the Hamas attack on Oct. 7 that left more than 1,200 people dead and nearly 250 kidnapped, and sparked a war that still rages more than two months later. More than 20,000 people have been killed in Gaza so far.In the weeks that followed the attack, Silver’s sons, Yonatan and Chen Zeigen, tried to square their mother’s moral crusade with their desire for justice.International investigative correspondent Kevin Sieff was there, too, following the brothers as they asked an impossible question: In the wake of their mother’s murder, is peace still worth fighting for?