ninenicknames I am going to tell you what I would do and you are very free to ignore me!
Just for the record I have a dd who is very dyslexic with autistic tenancies (birth daughter) and was very difficult between about age 5 and 8.
I've also got a very emotional adopted son, (aged 6).
This is some of what has worked for me (us).
-Do no waste time with people who in any way belittle you or your child, unless you are stuck in social situations with them (in which case keep a cool distance).
-As she is queen bee you do not need to piss her off unnecessarily, or confront her. You just need to lesson off the time you spend so you are not spending any time with her alone/with kids and only see her when she is in a group.
- Do not share with her about your child! She does not understand. Her child is currently quite compliant. The child may or may not always be so - but she is not someone who can help you and she will only made you feel bad (unnecessarily!)
- speak to your health visitor or school's link worker when your ds is in a school/nursery and be open to professional advice. This advice should be based on evidence of what works for young kids and not on outdated modes of how to guilt children into behaving.
It' a one day a week, 10 week course, and is excellent.
This course may be offered free in your area and even offered with a free creche - you may need your health visitor or schools link worker, in future, to refer you. The book should come free with the course.
Or book could be borrowed from a library, the library should be able to order it for you (it is so good you can say it comes highly recommended).
I did this 4 years ago and it is brilliant. It is not about blackmailing your child with Father Christmas.
-I am dyslexic and hate books with a passion but highly recommend this one, [[https://www.amazon.co.uk/How-Talk-Kids-Will-Listen/dp/1848123094 How to talk so children listen and listen so children talk]]
-Your son may simply be a bit angry and a bit rude, and if you are able to consistently follow some of the guidance for 'take a break' (time out but very short, no big 'sorry' and really just 2 minutes to get their mind of what happened), and lots of building him up etc, modelling polite speech etc (which I am sure you do already) he may just naturally grow out of 'it'.
My dd was a very angry and emotional girl and it was not until she was about 8 that I really begun to get a handle on it (it started when she 5, especially at 6 - but did appear eariler, so we had two years of lots of emotions and now, she is 12, things have got steadily better).
-Lastly, be open to the possibility your son may have some additional reason like ADHD, ASD, etc, which might be making things like they are. If he does, you can still learn what helps him (and you) to cope. He will still be your little boy; and one day your great big grown up son. But you will feel better knowing that there are some circumstances outside of your parenting which may cause things to be this way. If this is not the case, and it may well not be the case, then eventually your parenting will win him over and he will calm down, I think IMHO.
I'd also be tempted to find some cartoons or story books about manners, and rudeness, and get him to identify what is rude behavior, and why it is unhelpful, and how to change it. If he can identify for himself what the problem is, he will learn better.
childrensbooksguide.com/manners
Good luck. 