Baby P's sadistic "stepfather" has been jailed for life after a campaign of abuse against the little boy and the rape of a two-year-old girl.

Little Peter's mother was jailed indefinitely and told she would serve at least five years for causing or allowing her son's death.

Peter was 17 months old when he was found dead in a blood-spattered cot in August 2007 having suffered a broken back and fractured ribs.

He had more than 50 injuries despite being on the at-risk register and receiving 60 visits from social workers, doctors and police over eight months.

The 32-year-old stepfather, who cannot be named for legal reasons, was told by Judge Stephen Kramer he would serve a minimum of 10 years. This will run concurrently with a sentence of 12 years for his part in Baby P's death.

The mother, who is 27 and also cannot be named, begged the judge for mercy on Thursday as she apologised for "letting down" her "darling" son.

The mother, her boyfriend, and lodger Jason Owen, 37, of Bromley, Kent, were being sentenced for causing or allowing Peter's death. Owen was also given an indeterminate sentence and told he would serve at least three years.

Peter's natural father told the Old Bailey on Thursday of his horror at the knowledge that the little boy suffered months of pain, fear and loneliness before his death. He said his life had become a "living nightmare" since losing his son.

In a victim impact statement the father, who cannot be named for legal reasons, told of the moment he was confronted with his son's lifeless body in a north London hospital. He said: "I could not believe what was happening. I could not believe it was my son."

Peter's death sparked an outpouring of public anger and led to strong criticism of the social workers, police officers and health professionals responsible for protecting him. Five employees of Haringey Council in north London, including children's services director Sharon Shoesmith, were sacked and the General Medical Council has suspended two doctors involved in the case.