The thing is that was long before we had a little guy running around and now since he's at the age where he's walking around and loving on the dogs I would rather not use any harsh chemicals on the dogs that could end up on him or in his mouth from loving on them. Second, Frontline in the last two treatments seems to have no affect on fleas. According to several people around this area is that fleas are becoming immune to it. Newer chemicals are suggested instead - but that goes back to my first concern - my son. Those of you with dogs, what other methods have you tried, if any, that works great without the need of putting chemicals on the outside skin?