but I would also add, that you may need to repeat this step multiple times. the life stage of a flea is about 21 days. so you may kill all the adults and babies in the first round, you could have new fleas hatching within weeks or days. it sucks. we had a bad infestation about 3 years ago. had to bring all the pets (8 total) to the shop, clean house, yard and car. then we repeated the whole process two more times in 6 weeks. we may not have needed the last one, but I wanted to be sure. then you need to find a preventative, frontline, advantix, or the like. flea collars are only good to drop in your vaccuum. good luck.
