i knew a guy who did exactly the same, police were called several times by several people, nothing happened, the mother denied all knowledge and his son claimed it was his girlfriend, not his dad's. one day we smashed his car up and knocked his front door down. one of my mates chased him round the house with a knife. guess what? cops show up and arrest 2 of my mates. you try to do a service to society and thats the thanks you get. he had to keep moving house to avoid people, think he's in leeds now. i know of 2 under12's he has definately had regular sex with. there is nothing the police can do, its your word against theirs. credit to the cops though, they only dished out cautions, no further charges. turns out he stayed with the second victim, and as far i know they are still togther, last i knew they were living together in a caravan. she's over 18 now.