I'm with Zizek on this stuff.

> “Imagine you or me, I’m a small boy. It’s Sunday afternoon. My father wants me to visit our grandmother. Let’s say my father is a traditional authority. What would he be doing? He would probably tell me something like, “I don’t care how you feel; it’s your duty to visit your grandmother. Be polite to her and so on.” Nothing bad about this I claim because I can still rebel and so on. It’s a clear order.

> But what would the so-called post-modern non-authoritarian father do? I know because I experienced it. He would have said something like this, “You know how much your grandmother loves you, but nonetheless I’m not forcing you to visit her. You should only visit her if you freely decide to do it.” Now every child knows that beneath the appearance of free choice there is a much stronger pressure in this second message. Because basically your father is not only telling you, you must visit your grandmother, but you must love to visit it. You know he tells you how you must feel about it. It’s a much stronger order.”

I'm not sure this applies. In the prior case they were talking about recognizing emotions and asserting rules (with explanations). I think Zizek's example here is more about disguising a direct order as a way to obfuscate authoritarianism. I don't think OP is saying that you should use subterfuge to get your way, but instead that you should recognize negative emotions as they happen, by explicitly noticing and talking about them out loud.

I think that if OP were to use the approach Zizek mentioned, they would've said something along the lines of: "You don't have to take off your dirty shirt, but oh the bed would be so sad if you were to wear it, really you would be the most beautiful child if you were to take off your dirty shirt and put a clean new one".

There's another way of handling it - remind your son that his grandmother would love to see him, and if he doesn't want to go, let him. Maybe from his perspective he doesn't feel very loved by his grandmother. If he did, he would probably want to go. Problem solved. No demand is made on the child to either do something he doesn't want to do, or to feel some way he doesn't actually feel.