The police were called to a flat in Hostein Way just before 3pm on March 11 after worries about the welfare of those inside.
After going inside, emergency services found a man and woman with serious injuries, who died at the scene.
They have been formally identified as 51-year-old Michelle Mileham and the man who died was 53-year-old Gordon Mileham – brother and sister.
The cause of death has been given as stab wounds.
Michelle’s death is being treated by police as murder, while Gordon’s death is not being treated as suspicious.
The police are not looking for anyone else in relation to the incident and both of their next of kin have been informed.
An inquest will open on 10 April at Croydon Coroner’s Court.
