Rules for siblings

[Tillytoes14]

Hi,
I have two children 4 and 9. They have their great days where they can play calmly and nicely together, but we have an awful lot of days where they argue, which is fine to a degree, but recently they have started to name-call a lot, this includes names like stupid, loser and sometimes idiot. Also my oldest son taps his younger brother on his head a lot, or ruins something's the younger one is doing, like if he's making a den, my oldest son will ruin it etc. I've tried telling my oldest to set a good example, so if my youngest name calls to tell him not to do it and walk away, but my oldest will name call back to his brother, so it tends to be a constant cycle and I find I'm refereeing all the time, which is pretty exhausting. Do you have rules for your siblings, if so what consequences do you implement?

Thanks in advance.

What do you say to DC2 when he name calls?

I tell them both if they repeat it, they will go to their rooms, which they do, it's getting a bit better, but I think I need a consequence that will have a bigger effect. I do think they need some rules with clear consequences though, in order for them to gain a bit more respect for each other, although they do play and are kind to each other too, it's just I don't want it to become a pattern, where it gets worse.

I was just asking as it seemed from your post that dc1 was getting all of the flack and dc2 wasn't being told.

We have had a lot of arguments at the beginning of the holiday but recently we've been giving them jobs to do together, once the jobs are done they can play. It's helped them to get along a bit better.