Métis foster parents fighting to keep a nearly three-year-old Métis child they've raised since birth have lost what could be their final battle in B.C. Supreme Court, CBC News has learned.

Late Wednesday, Justice Barbara Fisher rejected the latest bid by the foster parents — back by the birth parents and the BC Métis Federation — to try to stop the B.C. Ministry of Children and Family Development from removing the child.

Fisher's ruling comes after two days of hearings last week.

In her decision, Fisher ruled the bid to keep the child in B.C. with the foster parents was "an abuse of process," because of the number of actions the couple had launched in the past year.

The girl can only be identified as S.S. under a court-ordered ban.

On Sept. 13, the B.C. Court of Appeal also rejected an attempt by the foster parents to identify a gap in the province's adoption act that would have allowed them to adopt the girl.

Following that loss, the foster parents had to surrender the child to the ministry on Sept. 18.

The latest court decision clears the way for the ministry to send the child to Ontario to be adopted by a non-Indigenous family, who are the adoptive parents of the child's two siblings.

The child can now be flown to Ontario in the next 24 hours.

S.S.'s foster parents, birth parents and the BC Métis Federation had fought the removal in court, arguing that the child should remain in B.C. and be raised in the Métis culture.

They had also argued that keeping the child with the foster parents was in the best interest of the child.

Numerous challenges

In asking for a judicial review, the birth parents had claimed they had already placed S.S. in the foster parents' care, by conducting an "Aboriginal custom adoption" in December 2014 that was outside the power of the courts and B.C's director of of child services.

But late Wednesday, Fisher ruled the latest court challenges were an abuse of process, due to their number and conflicting nature — and that some recently raised arguments should have been contained in earlier court actions that were argued and lost before other judges.

'It's been a tough, tough day.' — Foster mother L.M.

"The foster parents should not now be permitted to bring forward a claim that their counsel decided not to press or pursue in these prior petitions," wrote Fisher, "and the birth parents should not be able to do so, either.

"I consider this to be an example of litigation being conducted in a piecemeal fashion and in a manner that undermines the integrity of the judicial process," she said in her decision. "Therefore, regretfully, I must conclude that the petition… should be struck as an abuse of process."

'She was so sad'

Reached by CBC News by email, the foster mother, who can only be identified as L.M. to protect the identity of the child, said: "It's been a tough, tough day.

"We saw S.S. this morning [before the court decision] and she was so sad and wanted to come with us.

Foster parents Metis toddler

The tot's foster parents, who also cannot be identified, vow to take their fight to the Supreme Court of Canada. (Michael McArthur/CBC)

"Aboriginal law is supposed to be upheld in Canada so she is legally our daughter, but they have taken her by force, which is against the law," L.M. wrote.

The foster parents say they will now take the case to the Supreme Court of Canada to seek an emergency application to prevent S.S.'s move to Ontario, but they concede "our daughter will already be on a plane."

Still, they vow to fight on.

"As far as [the ministry] is concerned, we have seen her for the last time, We'll see about that."