A judge has refused to make an order barring five children from formally becoming Catholics.
Mr Justice MacDonald heard that the children, who are aged between 11 and four, had been taken from their Protestant mother's care and placed with their Catholic aunt.
The children's aunt, who has been caring for them for more than three years, wants them to be baptised into the Catholic faith.
Their mother objected and asked the judge to make an order barring their aunt from having them formally initiated as Catholics until they were 16.
She said they should be "able to choose their own religious path" when older.
Mr Justice MacDonald has refused her application.
The judge, who is based in London, has outlined his conclusions in a ruling published online following private hearings in the Family Division of the High Court.
He said the children could not be identified.
Salford City Council, in Greater Manchester, had responsibilities for the children's welfare, he said.
Mr Justice MacDonald said the family also had links with Norfolk and Suffolk.
The judge said the children had been informally attending Catholic services and events for some time.
He concluded that denying them "the option of participating in formal rites of passage" would be wrong.
The judge said evidence showed that if such a bar was imposed the children might see themselves as "different" to the community in which they were living and feel "segregated" or "excluded".
He said he was not pronouncing judgment on the "relative merits" of the Catholic and Protestant religions but deciding what was in the best interests of the children.