Flea life cycle:
Brand new flea jumps on pet. Starts biting. Starts laying eggs in a day or so.
Eggs fall off pet into carpet/dirt/couch/bed/etc. Eggs hatch into larvae.
Larvae eat adult flea poop, which also falls off pet.
Larvae turn into pupae and wait for ideal conditions to hatch out.
Vibrations, increased carbon dioxide, temperature, humidity stimulate pupae to hatch out.
Brand new flea jumps out of pupa and lands on pet. Fleas rarely, if ever, jump from pet to pet. All fleas on your pet are brand new fleas.
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("pet" in this post means "dog or cat")
Frontline and Advantage last about 3 weeks each for near complete kill (they kill some but not 95+% after that), and less if the animal is bathed or swimming a lot. Revolution for CATS (not for dogs) seems to last the full 4 weeks at better than 95% kill. I don't know about the other topicals (and there's a million and one new ones) because I don't use them; most seem to be safe and effective, but I haven't looked at the studies. If you're using anything that doesn't last the full 4 weeks, you either need to be applying more frequently (most of these products are safe up to every 2 weeks, check with your vet) or you need to cover the "gap" some other way (I like having Program/Sentinel as the background flea control on all pets using Frontline or Advantage).
OTC topicals work on fleas - but usually not for very long, and tend to be much less safe (but much cheaper) chemicals with increased risk of side effects, especially in cats. Flea collars don't work (well, they work around the pet's neck, but since most fleas seem to like the back half of the pet, and there's more to a pet than their neck, probably not useful). Flea shampoo works... while the shampoo is on the pet. All take several hours of flea contact with the pet to die. Which means the fleas can bite a few times. Usually takes 24h of flea on pet to start laying eggs, and all these products do kill faster than that.
Comfortis is a monthly chewable tablet for dogs (big pill, some dogs don't like flavor, can crumble into food and most dogs will take it that way). Capstar is a daily tablet for dogs and cats. Flea bites once, flea dies. Very effective kill, especially if you've got a very flea allergic pet.
Lufenuron (the drug in Program and Sentinel (Sentinel also has heartworm preventative)) is flea birth control. The drug is in the pet's system; the flea bites the pet, lays its eggs, poops its poop... but the eggs don't hatch and the larvae that eat the poop have trouble pupating properly. Decreases the numbers of eggs and larvae and pupae in the environment.
Effective flea control requires not just killing adult fleas but also the larval and pupal stages in the carpet/dirt/whatever. Good adult flea killing is important - I put dogs on Comfortis and cats on Revolution, but every vet probably has their own protocol. So now what you have to do is worry about the immature stages in the environment. If you wait (usually not more than 2-4 months) and keep the pets on good flea control, the eggs that are left will larvate and then pupate, and the pupae will hatch out into adult fleas, die when they bite the dog or sit on the cat a few hours, and in theory, you will have no new eggs in the environment.
You want your pets to turn into flea killing machines - let them go around the house, stimulate pupae to hatch out, and kill the fleas!
At this point, if you have "normal" dogs and cats, you can switch the pets onto a Program-only system - any new fleas they happen to pick up by wandering through the bushes and stimulating a pupa to hatch out will not be able to reproduce. A couple fleas on a dog or cat typically doesn't bother them much. A severely flea allergic dog or cat will need to be on a fast-acting adult flea killing product because that can be all it takes to set off their allergies.
Flea powder in vacuum works, but I worry about some of the flea powder being aerosolized expelled out into the air and being inhaled. Same with the flea-collar-in-the-vacuum-bag trick. Flea bombs and the like also work. But good flea control along with patience will as well.
Vacuum frequently to stimulate pupae to hatch out and decrease some of the eggs and larvae. Wash bedding/upholstry that can be washed (including the cushions). Let things sit in the sun for a day or two. But ultimately, good flea control on your dogs and cats is the only way to go.
For effective flea control, EVERY POTENTIAL HOST needs to be treated, or else the fleas are just going to breed on the one critter that hasn't been treated.
Most of the products I've mentioned are prescription products; talk to your vet about them.
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Ash, when you say "kids," do you mean fur-kids or human-kids? Fur-kids of what species? And what species are Lady, Spirit and Speed?
