A father, aged 41, who was found guilty of 16 charges of rape, indecent assault, buggery, cruelty and indecency, was jailed for life with an order that he serve a minimum of 12 years. He was said to have 'behaved like a monster'.
A 67-year-old grandfather, who has already served a prison term in connection with the sexual abuse of another child, was jailed for a total of four years on three specimen charges of rape and indecent assault.
His son-in-law, aged 31, received a total of 12 years imprisonment after he was found guilty of three rapes, two indecent assaults and cruelty.
The fourth defendant, a 29-year-old mother, was jailed for a total of 18 months after being found guilty of indecent assault and cruelty.
The offences took place between 1978 and 1989 and involved four boys and three girls from the same extended family in Ealing, west London.
During the three-week trial, the court was told how the children were beaten into submission. One boy was held by his ankles from an open window to force him to agree to sex acts, and an 11-year-old girl was forced on to the streets after dark to search for discarded cigarette ends. Two of the children tried to commit suicide.
Passing sentence, Judge Brian Capstick QC, said: 'It is about as dreadful a case as I have encountered . . . You have all behaved appallingly. It's a pity that you cannot be named, but at least some of the horror for the children can be saved by their not being identified.'
Detective Inspector Carol Bristow, who led the police investigation, said the victims, now aged between 11 and 21, had all been left severely emotionally scarred by their ordeals. She said it was probably the worst case of sexual abuse uncovered in Britain.