A millionaire restaurateur was stabbed to death by her own grandson after he became concerned about the amount of cannabis she was smoking, the Daily Mail reports.

69-year-old Sue Addisowner of popular Brighton restaurants Donatello’s and Pinocchio’s, was attacked by her grandson, Pietro, while at her £1million home.

He stabbed her at least 17 times with two knives, causing fatal injuries to her chest and neck. Lewes Crown Court heard he allegedly called 999 and said: “I’m calling to surrender. There was a murder.”

19-year-old Pietro Addis was a student with ambitions to become a chef while working in the family restaurant. His grandmother was well known in Brighton’s business community, her restaurants starting in the 1970s.

Her three sons, Leo, Stefano and Mikele all worked at the restaurants, which were among the most popular in the seaside resort and attracted celebrities such as actor Bill Nighy, model Katie Price, actress Michelle Collins and a host of Premier League footballers.

The 19-year-old’s lawyers said Pietro had been diagnosed with ADHD and had been prescribed medication for the disorder. But in addition to taking the prescribed medication, he had also started smoking cannabis and taking anti-depressants and his behavior had worsened. The court also heard that he smoked one or two cannabis cigarettes in the evening, three or four times a week.

The teenager lived with his father, Leo, and stepmother during the pandemic, but after a fight he moved out and went to live with his grandmother.

His grandmother had told his friends, Sue Eastman and Denise Taylor, that she was becoming increasingly concerned about her grandson’s use of cannabis. The trial is not over.