The judge said it was impractical to ban the term
An Australian court has rejected a mother's request to ban the use of the term "mummy D" to refer to her daughter's step-mother.
The woman separated from the father before their daughter turned one, the Sydney Morning Herald reported.
She had told the Family Court that encouraging the daughter to use the term was "an incendiary action".
But the judge said it was impractical to stop the father from encouraging the child and step-mother to use the term.
The father had already agreed to use the initial of the step-mother, D, and not encourage the use of mum or mummy, the newspaper reported.
Justice Christine Dawe said that the use of the expression by the stepmother "would [not] undermine the mother's relationship with the child".
She also said that the child may possibly "adapt to calling each of her step-parents by their first names rather than using expressions of either 'mummy' or 'daddy'.''
The judge said that details of names used are usually agreed outside the court, but ''in this case, it has not been possible''.
A family law expert from the University of Sydney said it was the first such case he had heard of.