A nurse who performed on Britain's Got Talent as part of an NHS choir after her son's death was fatally stabbed in her home.
Scotland Yard, who have arrested a man on suspicion of murder, named the 31-year-old woman found with a knife wound in Battersea, south-west London, as Simonne Kerr.
She was a nurse working for Guy's Hospital, near London Bridge, and had appeared on the talent show with the B Positive Choir to encourage blood donations.
The haematology and oncology nurse at the time told how the performances gave her strength after losing her son Kavele to sickle cell disease, a blood disorder.
A 40-year-old man remains in police custody after being arrested at the scene in Grayshott Road, the Metropolitan Police said.
Officers said Ms Kerr, whose death sparked the 90th homicide investigation in the capital this year, was living in the flat but was originally from Wembley, north-west London.
Police were called shortly before 12.40pm on Wednesday to the Victorian terrace but she was pronounced dead at the scene despite the efforts of paramedics.
Vickie Foot, a 43-year-old who lives nearby, described the killing as "absolutely shocking" and said she saw the arrest.
Police reassured residents, telling them: "It's not gang-related."
Scotland Yard said detectives are not looking for any other suspects.
The woman's next-of-kin have been informed and a post-mortem examination was due to take place on Thursday.
