My 5 month old started vomiting up blood yesterday. First it was clear, then pink and then red which was the blood. The vet can't find anything in the x-rays and today when we called the vet, we were told the cat did not vomit the entire time it was there. My husband just called and told me that the brother to this kitten died 2 weeks ago from the same thing. Does anyone know what this could be? Should I be concerned as well for my 3 children?