A London council's policy on payments to foster carers is unlawful, a High Court judge has ruled.
Mr Justice Males said Tower Hamlets council was wrong to differentiate between foster parents who were related to children they cared for and foster parents who were not.
A woman who fosters two nephews and a niece complained she was paid less than an unrelated foster parent would be.
The judge called the woman one of society's "unsung heroines".
Mr Justice Males concluded Tower Hamlets council's payment policies were discriminatory, following a High Court hearing last month.
The woman, who cannot be identified for legal reasons, complained that Tower Hamlets council's policy was a breach of "ordinarily principles" of public law and constituted unlawful discrimination.
Tower Hamlets disputed her claim and said it was "not alone" in making additional payments to unrelated foster carers.
Council officials said unrelated foster parents were paid more because the demands and requirements placed on them were generally greater.
They said unrelated foster parents were, for example, required to attend more training courses, were frequently expected to take in children they knew little about in emergencies, and usually had to make longer school runs.
Mr Justice Males ruled in the woman's favour but said he "did not doubt the good faith" of the council.
The judge described the woman who brought the claim as "one of the unsung heroines" of society.
He said the children she cared for were "damaged and difficult" and "extremely demanding".
She had given up her job to look after them, provided an "excellent standard of care" and gave them a "safe and secure" environment, said the judge.