Dog gets stem cell transplantBAINBRIDGE ISLAND, Wash. (AP) -- Darrell and Nina Hallett love their dog Comet and have reached deeply into their wallets to prove it.The couple spent $45,000 on a stem cell transplant for their golden retriever, who is recovering from lymphoma, a type of cancer that attacks the immune system.Dr. Edmund Sullivan, a Bellingham veterinarian, performed the transplant last summer, using stem cells from another golden retriever.Sue Hendrickson, a friend of the Halletts, owns Comet's mother and 11 other dogs. She spent months tracking down 40 of Comet's relatives to donate blood, eventually finding three perfect matches....