Your kids need to be more respectful to you. Mimicking is never nice - not even to their peers. But it is certainly unacceptable to do a parent. You can laugh once or twice just to be friendly but after that say something like, "you know fellas, it's not nice to copy people - they don't always like it and you really should never mimic grownups. So please don't do it anymore." The next time they do it, repeat that statement and then add a warning something like, "I told you before that it's not nice......etc and from now on when you mimic me, such & such will happen to you (see Raise Your Kids without Raising Your Voice for ideas for negative consequences). Be sure to name a specific negative consequence that you are willing to carry out. The third time, and all future times that they mimic you, they receive a consequence (use the same consequence you originally mentioned 3 or 4 times. If the mimicking behavior is not decreasing, then choose another consequence and use it for the next 3 or 4 occasions). When you get serious about their behavior, they will too!  Sarah Chana