I have two small children who are often on the rugs and carpet in our house. However, I have now witnessed two instances of fleas hopping on my children so obviously we have a problem. Are the flea granules the safest to use in my instance? And do they ruin the rugs (we have a couple of pricey orientals) if I use it? Does the product eventually get vacuumed out or dissolve or stay in the rugs and carpet forever?