kitten 7 weeks weak not eating

Question
Our 7 week old kitten (hand raised)has had his vaccinations and worming.  He will not eat (I have to stick bottle in the side of mouth just to get liquid in him) he is very weak and will not play with the other kittens.  His heart beat is very fast and seems to have fast labored breathing, he will just sit and stare.  I have taken him to the vet 3 times--he will have the above symptoms for about 3 to 5 days then he will "miraculously" be fine and will eat, play and seem normal.  THen a few days later hes back to the not eating and seems like hes going to die.  I asked the vet if he thought he had FIP but he said no.  
All of his siblings are fine--running playing eating.  I am very worried--each time he has these symptoms--he seems so weak and sick that he might die.  
Please help
sincerely
pam bishop


Answer
Pam you need to see another vet for a second opinion.

that kitten should have bloodowrk done as well as a felv/fiv test.  if those were not done, your vet is not doing his job.

he should also have chest xrays done to be sure its not a heart problems or a lung issue.