Lynne Chafin did not see Eris for 10 months while the custody case played in a federal court in Alabama. She was allowed to return to the United States on a special visa just long enough to have a federal judge rule in her favor, allowing her to take Eris back to Scotland where they remain.
"I would like the Supreme Court to say that my case is moot," she said from her home. "If they don't, if they rule in my husband's favor and he is allowed to appeal then this is going to go on for years which is ludicrous. None of us will be able to move on with our lives, we're stuck in this constant state of appeals, appeals, appeals."
But Jeff Chafin and his lawyers say the federal courts are at odds over what judges can and cannot do over the "habitual residence" question. They say in this case the full appeals process was not allowed to continue, denying the father his due process rights.
"The phrase miscarriage of justice comes to mind," said Michael Manely, the father's attorney. "The other side's position is once a child leaves the boundaries of the United States, it's over. There is nothing you can do about it. And that has terrifying consequences."
Justice Sonia Sotomayor has unusual experience with this issue. As a federal judge on the 2nd U.S. Circuit Court of Appeals, she dissented from a decision that she said too narrowly interpreted the impact of a custody order.
She wrote in 2000 that the Hague Convention must have power to enforce a custody order that "by its very nature limits each parent's unilateral decision-making power, including his or her power to relocate to another country with the child."
In an unrelated 2010 high court case, Justice Sotomayor succinctly summarized the delicate balancing courts around the world must maintain.
"The purpose of the convention is, which court will decide the life of that child," she said. "And to avoid, as I understood the convention structure, this flight from court to court and this long, drawn-out process from country to country over who's going to make that choice."
Both sides agree clarity on the issue is needed, if not for them, then for other parents in similar situations.
"Ultimately what's at the heart of the treaty is the welfare of the child," said Cullen. "And it's not good for a child to be like a ping pong ball going backwards and forwards between different countries. And that's why the treaty solves a problem."
As for the Chafins -- still technically married but apparently never again to be husband and wife -- both share a measure of regret over their broken union and a child caught in the middle, as well as anxiety over what the high court will do.
"I believe that if my daughter's returned to the U.S., I will never see her again," said Lynne Chafin, who said this fight is about Eris' future and well-being.
Jeff Chafin is equally determined. "I'm going as far as I can. Until I humanly, possibly cannot go any further, I will not stop fighting for my daughter."
The case is Chafin v. Chafin (11-1347). A ruling is expected by the spring.