“I remember, a few hours after my children died, I stood outside the house where their lives had ended and thought desperately about the last time I spoke to them, held them, kissed them. I thought about all the things I didn’t get to do. Carla, who was three, had asked me for a snowman. Darragh wanted me to coach local football, and Conor was excited to set up his YouTube channel. In that moment,...