A woman has been jailed for life for murdering her sister before taking an expensive watch from a north London flat, the BBC reports.Nancy Paxton, 70, was found guilty of murdering her sister, film director Jennifer Abbott Downward, at the victim’s home in Camden in June last year. He must serve a minimum of 22 years.Abbott, 69, was found dead in his living room a few days after the attack, with injuries consistent with a violent attack. Her mouth was taped shut and the gold Rolex watch she regularly wore was missing.The court heard that Paxton had met his sister on the day of the murder and left the property about an hour later. He was arrested several days later, with the stolen watch later recovered from his belongings.Sentencing him, Judge Anuja Dhir KC said the nature of the attack showed clear intent.“Given the enormity of the attack I am sure you intended to kill your sister,” he said.The judge said Paxton’s actions after the murder showed a lack of remorse.He said, “Your actions and conduct after the murder show not only your absence of remorse, but also a deliberate and callous attitude towards what you did.”He also described the action of taping the victim’s mouth as humiliating.“This humiliating act was deliberate,” he said. “It was heartless, humiliating and cruel.”The court heard the victim suffered defensive injuries as well as multiple stab and cut wounds.Concern grew when a neighbor noticed unusual silence in the flat and forced entry, where Abbott found no response. His pet dog was trapped inside.In a statement, Abbott’s son described the murder as a “monstrous” act and said losing his mother was an “incredible nightmare”.“She was my hero and my idol,” he said. “She was my whole world.”Prosecutor representatives described the case as extremely disturbing, while detectives said the sentence reflected the seriousness of the crime.Detective Inspector Barry Hart said: “The sentence handed down today reflects the seriousness of this murder and ensures that Paxton will spend substantial time in prison.”Police said Paxton initially denied involvement, but evidence collected during the investigation led to his conviction.