I bought a Pomeranian puppy from a pet store last year. She was sick with kennel cough and loaded with fleas. I have since spent hundreds in vet bills, not only for her, but also for my other dogs, who caught her kennel cough. The pet store's guarantee says I have a right to be reimbursed for the puppy's vet bills (though they haven't yet paid). But can I also sue them for the vet bills for my other dogs? 

Sounds like you purchased a few more creatures than you bargained for: one dog, 100 fleas, and countless germs, all for the price of one!

It sounds like the pet store's guarantee clearly gives you the right to reimbursement for the veterinary bills you incurred for treating the puppy you bought. Some states laws also give you similar protection. If the pet store doesn't come through, you can sue in small claims court for the money due you.

Whether or not you can also get the pet store to pay for treating your other dogs is less clear. Start by having a look at the relevant state statute. But in any case, if you go to small claims court, you could certainly make the claim that the pet store was negligent -- that is, unreasonably careless -- in selling you a dog with a highly contagious disease, and that the store's action cost you money.

Your situation is, unfortunately, not uncommon. All too often, dogs bought from pet stores are sick -- that's why several states have enacted special laws to protect consumers. Next time you're in the market for a dog, find a reputable breeder and pick out a puppy that has spent its first few months being well-cared for by loving owners, not huddling in a pet store's cage. Or better yet, contact a rescue organization and pick out a homeless dog to be your companion. There are lots of purebreds and mixed breeds just waiting for good homes.