Hmmm, hate to admit it but...
I actually yelled at DD6 to shut up the other day because of this issue.
She laughed and did actually shut up for a few minutes.
She asked me for help on something and then proceeded to analyze my every move, critique me and my method of helping her and chat away, I just couldn't take it anymore.
Yikes.
Later I apologized but part of me realizes that it worked.