Is this a law suit(privacy act)?

My fiance is a legit dog breeder and our one dog had a bad pregnancy so we took her to get a c section at our veternarians office. My sister was with me that day, and she saw the vet tech who helped us that day the following week. My sister asked the girl how the surgery went and the vet tech started saying that my fiance doesnt know how to breed dogs and he bred the female with her brother which is NOT true! She is disclosing false and slandering information to the public and im pretty sure thats illegal. What can or should be done about this?