Want the best of The Telegraph direct to your email and WhatsApp? Sign up to our free twice-daily Front Page newsletter and new audio briefings. A top fire service boss hanged himself after arguing with his stepson over a birthday card, an inquest heard.Mark Smitherman, 55, was found dead in his home on Oct 16, hours after a visit from his stepson on the day of his daughter Isla’s birthday.The inquest heard that on October 15, Mr Smitherman’s stepson, Jamie – the son of his wife, Christian – visited the family home in Nottinghamshire on the evening of his half-sister’s birthday.An argument reportedly ensued between Mr Smitherman, who was chief fire officer at South Yorkshire Fire Service until retiring in 2011, and his stepson because Jamie had not brought a card.Assistant coroner Amanda Cranny told Nottingham Coroner’s Court: “There was something of a family history around the brother not bringing gifts.”Even though Isla had not been present and was out celebrating with friends in Sheffield, Mr Smitherman, who had over three decades’ experience working with the fire service, became “upset”.Shortly after going to bed, Mrs Smitherman returned downstairs and found her husband.A toxicology report revealed Mr Smitherman, who had retired from his management position at South Yorkshire Fire and Rescue Service in 2011, had consumed a “modest” amount of alcohol shortly before he died, which may have affected his thought process.Recording a narrative verdict, Ms Cranny said: “Mr Mark William Smitherman took his own life by hanging on October 16, 2016 at a time when his cognitive abilities may have been affected by the consumption of alcohol.”CORRECTION: This article originally stated that it was said at the inquest that Mrs Smitherman “attempted to justify her son’s actions”. This was incorrect. In fact, the Assistant Coroner expressed her view that it was Mr Smitherman – not his wife – who tried to justify his own actions and express his regret for the events of the evening. We apologise for this mistake, which has been corrected.