Petition Inappropriate Music Lyrics

Artists have been creating inappropriate songs which have rude lyrics. For example Nicole Sheringzinger with her latest song called Wet. Recently Rihanna has been told off for being too sexual and creating sexual videos which have been banned on some sites and rated 18. It is also claimed that she was making sexual references to a blow up doll. If you can ban videos then why cant they ban the lyrics? My problem is that younger children pick up these things and later on repeat them. This could be a influence to teenagers having sex before the age of 16 because they have seen music videos like these twp prime examples and want to copy off them. There are also many other artists in similar situations and i wish that the government would age rate them and not play them on the radio or tv before a certain time at night so children cant hear them.