Why can't we get rid of these fleas?

Our kitty had fleas. We got rid of them on her, and also put some frontline on her. She then went to the vet to be boarded so we could flea bomb the house. Well the flea bomb didnt work so we had an exterminator come. That didnt work either!!! I dont know what to do. Our kitty and dog are both flea free and on frontline and have no fleas on them, but the fleas keep coming on our daughter!! she is 1. she doesnt play outside since she cant walk. but how are the fleas still alive and how do we get rid of them?