Having read the post again, M0nica, I can see that the lack of speech marks confused me which is why I asked the questions. Obviously it wasn't as clearly elucidated as you seemed to think or I wouldn't have been confused. I did ask in a nice way. I just find the way things are written slightly difficult to understand instantly or even a second time I read them because I did go back to check before I posted. Obviously my brain was more woolly than usual.
I didn't say the hedge was running wild, I did manage to ascertain that the hedge was regularly trimmed. However, lots of people on here are asking why she doesn't just cut it back. If it marks her boundary she may not want to because it can cause confusion especially if the neighbours have a non linear boundary.
If her other neighbours are happy with where she parks and the hedge whilst the aggressive neighbour is unaffected, I see no reason at all why she should accept his behaviour. He is obviously a bully and I suspect that if she give way on this, he will find something else to make her suffer for as the 81 year old gentleman can probably attest to.
I make no criticism of her either for leaving disabled adult children alone either. It may well be that she had no choice or they would have been perfectly safe if the gentleman (I use the term loosely) had just left them alone.