Aliyah was jailed for four and a half years while Lacquan was handed six.
The court heard how the victim had been convicted alongside the pair for an assault in North London last year.
READ: MAN JAILED FOR MURDER OF GIRLFRIEND'S TWO YEAR OLD DAUGHTER
When questioned the girl, who cannot be named for legal reasons, admitted the crime and told investigating officers about the involvement of others in the attack.
James Dawes, prosecuting, said: “It is the Crown's case that's the incident which Aliyah Weeks believed (the girl) had snitched to the police.
“She had effectively told the truth in her interview about what they had done.”
Following this, Aliyah threatened the girl with violence saying “snitches get stitches.”
However she later changed her mind and told the girl she would perform a “line up” – performing a sexual act on a number of men – as punishment.
The court heard how then, the girl was taken to an alleyway and forced to perform a sex act on Lacquan.
“This was no childish folly. This was a wicked crime,” Judge Jeremy Donne said before he passed the sentence.
“This was a wicked crime and one that, Aliyah Weekes, you determined upon over the space of about an hour during which the victim was detained.”
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