When I brought my kittens in to have their first shots, I also got them some Revolution for fleas and gave it to them when I got home. After two weeks they had fleas again. Has anyone had this happen with Revolution? I went back to the vet yesterday and told them that they had fleas again and they gave me some Capstar to treat them until they can get a does of Frontline in a few weeks. She also gave me the Frontline for free which was nice. Does anyone prefer one over the other?