Um...why are the fleas still here???

Last night, I was on the computer and there was a flea on my arm!! YUCK!!! So, I decided to get the flea comb out and comb Noah. I saw at least 10 fleas on my little baby....poor thing!!

We used Advantage on Sept. 8th and then gave him a flea bath on Sept. 15th. I am pretty sure they were gone, but he wouldn't let us close enough after his bath to check.

After we use our 4 month supply of Advantage and start giving him flea baths every Saturday, will the fleas go away? I don't understand this...