Sorry I riled you, didn't mean to. Just passing along what I had been told. Body language means a lot to mine, if i put a stern look on my face and hands on my hips I don't have to hardly open my mouth. There was a documentary on human babies my mom had me watch today. They mixed up facial expressions with vocal tones. Confused the babies and fustrated them too. I have found with the children in my house that the higher pitched girls would say no and my dogs would think they were playing. I told them to say it firmly and with a growl, in our house it makes all the difference. Hope you find a solution, for no is such an important word. I also use a tone like the ehh or aaaaaa sharply that gets instant results from both chidren and dogs alike. I think dogs and small children are a lot alike in the fact that they know who is going to follow thru with the correction that goes with the command and act accordingly.