My kids actually played together for 2 hours without fighting
I know this doesn't sound like much but we have a 3 year old and a 6 year old who normally can't be in the same room for 10 minutes without arguing over something stupid. Today they built an entire fort with blankets and pillows and just hung out in it making up stories. I sat nearby pretending to read but honestly just enjoying the peace and the sound of them actually getting along.
Dude, that's huge! Two hours is absolutely something to celebrate with a 3 and 6 year old. We had similar chaos here and those peaceful stretches are gold. Whatever you did, keep doing it.