"The secret of change is to focus all your energy not on fighting the old, but on building the new," Dan Millman's fictional counselor Socrates said in Millman's Way of the Peaceful Warrior. This is profound and cannot be said often enough - I must have written several blog posts along those lines, all saying the same thing in different words.
The universe doesn't hear the word "no," it leaves it out, it simply ignores it; so do animals, people, and especially young children. Guess what they do when you say "Don't jump around on the couch." Guess what your cat does when you keep saying, with a look towards that couch, "Don't scratch that couch!" Guess what you do when the boss says "Don't do it this way." You'd rather not listen because it doesn't feel good being criticized. Besides, the boss didn't define how he actually wanted it done. But guess what you do when the boss says "That report was written just the way I wanted it, thank you for a job well done." You listen, you acknowledge, and you do more of the same because you love being praised and praise feels good.
So - when it comes to anything, be it children's behavior, employee behavior, your own health, life, define clearly what you want, not want you don't want, and move in that direction. Move forward instead of looking backwards. That way you get more of what you want because the universe gets it.