S.H.
.... at times, when my kids have been SO strong willed, and which kid isn't... what I did was a Mommy time out.
Meaning, if they did not cooperate or whatever and it was over the top, (I gauged it, it was for exceptions), then when they asked me for something/and had attitude with it... I said "No." And I added "If you cannot cooperate with Mommy and be a family member... then I will not, cooperate with you when you are being (insert behavior here)..." and I would walk away.
I told them that they CANNOT push their way around, just to get their way.
I told them, everyone has their limit. And this is it, for MOMMY. You being that way, is not okay. Mommy reached her limit, and that's it. I will not, cooperate with you or be "nice" when you are that way. And then I would walk away. And NOT give in, to any hissy fit or backtalk or anything.
I told them they can scream or grumble all they want, but it will not work. They are a PART of a family. They are not their own satellite.
A family is a TEAM. I also told them "you KNOW what that means. So act it. If you CHOOSE to be icky, that is your choice. But do NOT, make the day miserable for anyone else. It is YOUR, choice."
And I would walk away. Even sit down and read a magazine.
My kids KNEW... when I told them that, it meant business.
I told them, it is NOT okay. To be, and act that way... and they KNOW it.
When I took MYSELF out of the equation... and told my kids that I will NOT... cooperate with them, when they are like that... they instantly changed, their behavior.
And then I would tell them "see, you CAN control it. I am not fooled. I know, you know, darn well.... how to act or not."
Also while doing and saying that to them, I do not "argue" with them.
It is not a debate.
And, a kid needs to learn that they are not a special little snowflake.
Nor is one, when they act, that way.