Okay, before I get on my knees and beg for help / your opinions, I want to give you the facts.. - We experienced an outbreak of fleas in our flat having skipped Otto's (one year old male) monthly advocate dose. - We blitzed the house, he was quarantined and treated (temporarily with Frontline, no good!!). Then we used advocate, goodbye flea issue. - Took him to the vets on Weds night, turns out we've been using the smaller dose on him and he's actually a large cat now! Thought we'd wait to treat him again as had only treated him two weeks ago. - Nivali (female kitten) moves in on Thursday night. - I notice bights on my arm yesterday. Recall seeing a flea on one week old kittens at breeders house. Remember thinking, when she suggested using flea spray, that Nivali is definitely going on advocate. - No signs of fleas on Nivali, then or now! - Otto has fleas now.... Just now we treated him with the new larger cat advocate and have put him in the kitchen, washed the bedding and sprayed the bedroom. I am confused as to how they got to him again? Any ideas?? Maybe I carried a flea to our flat and he hadn't got enough advocate in his bloodstream? Nivali is going to the vet on Tuesday night to get her advocate and jab.