The trial heard that the children first came into contact with social work in Glasgow in August 2017 and were deemed to be at risk in July 2018.
But the allegations of violence and sexual abuse did not come to light until March 2020.
Police were alerted by a man who had got to know the children. One of the victims became hysterical when she mistakenly thought she had been shut in a room.
The man and his wife then documented details of what the children recalled happening at the hands of the gang.
Jurors were also told Owens, Lannery, Williams, Watson, Clark and Forbes – who was known as Scott the Cameraman – all had previous convictions but none were for any type of sex crime.
Owens, Lannery, Brannan and Williams were found guilty of attempted murder.
Charges related to causing the children to take part in seances and witchcraft were dropped during the trial.
More than 14 months after they were sentenced the gang returned to court for sentencing.
Owens was jailed for at least 20 years, Lannery for 17 years, Brannan for 15 years and Williams for 14 years.
Clark was sentenced to 10 years, Watson to nine years and six months, and Forbes to eight years.
Another woman, 40-year-old Marianne Gallagher, was convicted of one count of assault to injury but was cleared of all other charges.
Her sentencing was initially deferred for 12 months for good behaviour and returned to court on 6 January this year. She was spared further punishment and admonished by Lord Beckett after he heard Gallagher had not offended over the last year.
