We are having huge issues here, all we do is reaffirm to him how we speak (he is being rude at times) and that if he talks like XYZ I won't respond and I will literally turn away and ignore him and then turn and chat to DH or DD - sometimes works sometimes doesn't. Loads of praise works here as well, and I am getting him to do more things that he is capable of like putting cutlery away from thedishwasher etc. to keep him occupied as well as reaffirming that he can do stuff.

DS wouldnt' dress himself FOREVER - did my head in because DD was 18mths old and dressing herself "I DO IT" but recently we play a game where I go - noooo JJ doesn't know how to - all the while he IS doing it and then it's like he has tricked me. He thinks its hilarious but anyway, may or may not work. I remember DD going through a similar stage so am guessing they are going to grow out of it and it is a developmental stage where they are testing boundaries and exerting some independence!!