I am not a fan of "correcting" words - the exception being in therapy when I am physically teaching them how to say it. Just model them back so he gets lots of chances to hear them. Often kids can hear the words correctly before they know how to say them properly, so they think they are repeating them back correctly when actually they aren't - as Anne is experiencing! In those cases, correcting can be counterproductive. Just that extra modeling to help them figure out that what they are saying doesn't match what they think they are saying.
Me (40) DH (47) & furbabies * m/c 7/08 4/12 11/12