Six judges yesterday dismissed an appeal against earlier Family Court orders, launched by their aunt as litigation guardian.

But the girls, aged between nine and 15, are expected to remain in Queensland with their mother pending the outcome of ongoing Family Court proceedings. The high-profile case hinged on whether a Family Court judge denied the girls procedural fairness by failing to give them the chance to have separate legal representation.

The children, who cannot be identified, were born in Italy but hold dual Italian-Australian citizenship.

Their parents separated in January 2007 and later agreed to joint custody.

But in mid-2010 the children and their mother travelled to Australia and never returned, and their father tried to secure the girls' return under the Hague Convention's child abduction provisions.

The convention applies only to children younger than 16, and requires Australia to return the children to their home country so the custody dispute can be resolved.

In 2011 the Family Court subsequently ordered they be returned to Italy, but the mother appealed, setting in motion a legal stoush which reached the High Court. The full bench yesterday found there was ''no want of procedural fairness''.

Outside the court the aunt's barrister, Tony Morris, QC, said the case was the last resort when they lodged the appeal.

''The day when we applied initially in the High Court, my understanding is the girls would have been on a plane that evening,'' he said.

''So yes, it was perhaps a long-shot, but a shot that I thought had reasonable prospects of succeeding.''

It is expected the children will remain with their mother until the appeal is finalised.

Both parents were in the public gallery for the hearing. The childrens' father said through an interpreter he was ''very relaxed'' in the wake of the verdict.

The girls' legal team pointed to a 1996 High Court decision which ruled in such cases children should ordinarily have their own representation, provided they were of appropriate age and maturity.

But in 2000 amendments to the federal Family Law Act limited the availability of separate representation to ''exceptional cases''.

In the courtroom Mr Morris argued any person, regardless of age or disability, should have the right to present a case or respond to a case concerning their interests.

''There is, as it were, a prima facie right to be heard in the full sense,'' he said. Mr Morris argued procedural fairness should be the ''gold standard''. But Walter Sofronoff, QC, Queensland's Solicitor-General, said the position of children involved in litigation between parents could not be compared to that of capable adults.

He said children might lack legal standing and ''may lack the necessary development in thinking to meaningfully take part in litigation''.

''And indeed their development may be such that it would be abhorrent to consider them persons who would normally become parties to litigation between their parents,'' he said.