(LifeWire) -- Five years ago, Sara Vreed got embroiled in soap-opera-style custody arrangements with her ex-boyfriend -- and they don't even have children. What was at stake were the living arrangements for their 5-year-old canine, a Shetland sheepdog named Ivo.
Divorce left Jennifer Keene and her husband with one dog each and she later adopted Buffy.
"After we broke up, my ex got Ivo on the weekends," says Vreed, 31, an associate at an architecture firm in Portland, Oregon. "But it was really taxing on (the dog), and he started having a lot of behavior problems."
Things changed when Vreed's ex got his own Shetland sheepdog, Tuk, and the two pets became friendly during visits. Like children scheming to get their parents back together, the visitation led to a reconciliation, but even two cute pooches couldn't prevent a second breakup.
After round two, Vreed says the joint-custody arrangement was scratched.
"We had to split the pack and take the repercussions of whatever was going to happen," she says. "Spending time together with the dogs was not good for us."
Vreed is one of many cohabiting pet parents who have faced a sobering problem: Who gets the dog, cat, horse or boa constrictor when the relationship ends?
That question has sparked some human catfights; pet custody disputes in divorce are a growing area of the law. In a 2006 survey of 1,600 members of the American Academy of Matrimonial Lawyers, a quarter said they had noticed an anecdotal uptick in pet-custody cases in the past five years.
Unmarried pet parents
You don't have to be married to get mired in a pet tug-of-war. Adam Karp, an animal rights lawyer in Bellingham, Washington, says most of the calls he fields are from singles in their 20s and 30s.
Even among the unmarried set, these battles can carry high stakes and high drama. Take, for instance, a Washington state case in 2004, when Karp represented Ashley Wilson, the music director of a Seattle rock station and the owner of a boxer named Marley.
When Wilson, who was in her mid-20s, broke up with her live-in boyfriend, Todd Templeton, the couple agreed on a joint-custody arrangement for the dog.
Everything was fine until Wilson met someone else. Templeton "accused her of destroying the family and retaliated by hiding Marley," Karp says.
The case went to court and, although Wilson and Templeton were technically co-owners, the judge awarded custody to Wilson.
A pet prenup
Experts and lawyers say pet owners, married or not, must prepare for the worst-case scenario by laying out in writing what will happen if their relationship doesn't outlast Fido.
Elizabeth Elliott, a Seattle animal law attorney, says most pet owners neglect to do this, relying instead on a goodwill custody-sharing arrangement. "That works fine," she says, "until one party refuses to give the dog back. "
Karp warns anyone sharing a pet to be crystal clear about ownership. "At the beginning of the relationship, you really have the best expectations and think you are going to be together forever. But then the cops show up over who owns the dog or cat, and the law will most likely view the matter in terms of who has possession."
Ownership is defined by purchase or, in the case of a shelter animal, who paid the adoption fee, so the best evidence is a bill of sale or an adoption record, Karps says.
Elliott also recommends the agreement be enforceable across the U.S., "because what happens when one party leaves the state? You have to have the foresight to think about all the different scenarios that could play out."
The courts have yet to institutionalize the standard of "the best interest of the dog," as they have for children, but it's the benchmark experts like Jennifer Keene, a dog trainer and the author of "We Can't Stay Together for the Dogs: Doing What's Best For Your Dog When Your Relationship Breaks Up," advocate when it comes to working out new pack arrangements.
"I call it canine-centricity," says Keene, "which means thinking about how you can work together for what is best for the dog."
The extended pack
That's exactly how Keene, 31, and her ex-husband approached the end of their four-year marriage in 2005 -- they agreed on a split-custody arrangement. He got Sixxy, a 3-year-old pointer mix. Moxxy, a 4-year-old Australian cattle dog, stayed with her in Beaverton, Oregon.
The two still do what Keene advocates most strongly: communicate for the sake of the animal. "Just the other day we were talking about Sixxy taking a refresher obedience class and he wanted to get my input on the training style," she says.
They came up with their custody arrangement by considering each dog's personality. "If your dog is really attached to one of its owners, like Moxxy was to me, then it's going to be much more stressful for the dog to be separated from that parent," Keene says.
Keene hasn't seen Sixxy in years, but every year she mails birthday and Christmas presents to the pooch, who now lives three hours away in Washington state. "The little gesture of sending gifts," she says, "is one way I can stay connected to Sixxy."
LifeWire provides original and syndicated content to Web publishers. Hannah Seligson is the author of "New Girl on the Job: Advice from the Trenches." Her work has appeared, in among others, "The New York Times," "The Wall Street Journal" and "The Boston Globe."