Two women who had an "intimate relationship" are embroiled in a legal fight over the future of their twin five-year-old girls.
Judges have heard how the girls were born after the first woman donated eggs - fertilised by an artificial donor - so the second woman could become pregnant.
The judges have been told there were "scenes" as the women's relationship ended.
Since the split the girls have lived with the second woman - their gestational parent - but the biological parent wants to share their care.
The dispute has been analysed by a county court judge in Portsmouth and the Court of Appeal.
Now appeal judges say there should be a fresh hearing in a county court so a judge can decide whether to make a shared residence order.
Detail emerged in a written appeal court ruling published following a hearing in London.
None of the people involved were identified.
Appeal judges said the twins called the second woman "mummy" and the first woman a "pet name".
Judges said the women had become "mistrustful" of each other.
They said the first woman had suggested she was "going to see if she could have her story published in the press". The second woman's response had been that such a move was "calculated to distress her personally and embarrass her professionally".