My difficult child is now 18 and he's the middle child of 5. I parent him differently from the others. He wears shorts year round and will only put on long pants when going hunting or out to work in the snow. When he was in first grade, the school threatened to call CPS if we didn't make him wear long pants to school. They said he couldn't go out to recess if he wasn't dressed warmly enough. I left a coat, long pants, etc. at school and he was told he'd have to stay indoors if he didn't wear them. The school didn't do outdoor recess when it was below 32 (0 Celsius). It was his choice. Sometimes, he put them on and went out and others he didn't. The school was really upset but it was no longer a source of tension between us... His body temperature regulation is different from other people's. Ironically, babyboy 13 will no longer wear long pants to school.
The one thing I disagree on is please and thank you. I use those words to my kids all the time and I expect all of them to use them. difficult child is actually quite polite in that way. PC16 is not. Our kitchen is set up with a long table and easy child usually sits at the far end on the opposite side of the table. I sit where I can get up and get things. PC16 will say: "Hey, mom, can you get me X?" and I ignore him till he says please and I don't hand it to him till he says thank you. He will often argue with me that please and thank you are not necessary and I should know that he feels them in his heart! I tell him even if I feel them, I doubt any future employers will. My suggestion is to use please, thank you ,etc. whenever and wherever appropriate as I'm sure you do and to not respond to J unless he uses them. Get him the item when he says please and when he doesn't say it, say "I'm sorry, but I didn't hear you say please." Even when my difficult child was at his worst, the teachers would say that he was unfailingly polite about his resistance/refusal. "I'm sorry, Mr. teacher, but I just don't care to do that homework!" J is very young, if you model etiquette for him without hitting him over the head with it, you may get better results. As for shoes, etc., all of the clothing in my house was stuff that was appropriate and I didn't really care what outfits they chose to put together. I even let them wear sneakers to temple. If he doesn't wear the right type of shoes for an activity, he will be made to sit out by the adults in charge. difficult child almost missed a camping trip once because he insisted on wearing sneakers. I had put his boots in the car and offered them to him. He thanked me, took them and went.
It's not easy. I also recommend "the explosive child" for its box system. Behaviors are put into A, B or C by you. A is non-negotiable stuff - safety issues where you can not compromise. For instance, J wants to ride a bike without a helmet, no. Helmet on, have fun. If you catch him without a helmet, no bike for x period. B is stuff you want to work on or can compromise - politeness, and food intake - but it requires patience and alot of it, C is stuff that is unimportant - he wants to wear green pants and a purple shirt, so what. C is stuff it's not worth fighting over or where you can let him feel like he's won,
J has to live in the real world and what's cute or tolerable in a small child becomes less so as they age.