I know this is extremely common but DH and I are at our wits' end with our DCs' constant fighting. They are 9 and almost 4 which is a tricky age gap tbf, and to top it off the 9yo has SEN - currently going through the assessment process but ASD and ADHD have been suggested. He particularly struggles socially and has never been able to play alone or amuse himself, but he also really struggles to play with his brother who he finds annoying. DS1 has to always be right, always in control, etc. and we try tactics to help with this but it's only a matter of time before his frustrations boil over.
DS2 is particularly physical at the moment and resorts to hitting and kicking almost instantly. They constantly wind each other up and it turns physical so fast - it's not just name calling; they really lay into each other. If we separate them, DS2 in particular will want to seek out DS1 simply to start annoying him again. They fight over the TV, the trampoline, sitting next to each other in the car...occasionally they'll play nicely together but you can't just leave them to it really; you have to hover close by.
DS1 is quite jealous of DS2 and sees him as 'getting all the attention' (which isn't true; DS1 has always, from birth, wanted constant 1:1 adult attention which is tricky). We have explained that DS2 needs a different type of attention as he is only 3!
It has got worse since the beginning of the summer and not just at home - even at relatives' houses or e.g. on days out with grandparents. It's so draining and miserable! We do time outs, punishments, tellings off, etc. but still it continues. Has anyone come out of the other side of this or have any tips?