The family of 17-month-old Hugh McMahon say he died after swallowing a button battery from a children’s toy. His father, also called Hugh McMahon, recalls the last time he put his son to bed. It was Christmas Eve and Hugh had arrived at his home in Motherwell, North Lanarkshire, laden with last-minute shopping. He went upstairs, gently tucked in his young son and wished him goodnight. He...