I am as much of a continuity freak as the next fan which is why there are aspects of the prequel trilogy that drive me nuts. Of course Luke must be taken to Tatooine to live with the Lars, but semantically it does not make sense because they are not his family. They are his step family through his grandmother's re-marriage. His maternal family actually resides on Naboo. If Yoda truly wanted Luke to grow up with family, he would have been sent to live with his blood aunt Sola and his cousins Ryoo and Pooja. Sure, Tatooine is a better place to hide him from the Empire, so Lucas should have generated a better dialogue sequence.

Back in the day, there was a theory that Owen Lars was actually Ben Kenobi's relative.

My own revisionist theory which I have related in the past, is that either Owen or Beru would be Anakin's half-sibling, making one of them related to Shmi and therefore really Luke's biological family. In which case Yoda's contention would be accurate. As it stands he is just a crazy, old wizard.