When we brought Casco home when he was a puppy, he was our baby, and for three years, he was our only one. We doted on him. We made him birthday cakes. We gave him weekly baths. He rode shotgun in my VW beetle and I took him everywhere I possibly could. We taught our golden retriever to swim for crying out loud. And then, 6 days after Casco’s third birthday, we brought Thomas home.