My favorite comment from the article, and something I'll be trying on my kids:

"Our kids played upstairs in a bonus room. If I heard fighting I’d go upstairs and break it up, then proceed to find all kinds of things that needed to be cleaned. The bonus room was always a mess.

It didn’t take many iterations of that process before I started hearing fighting, then “shhh! Do you want dad to come up here and tell us to start cleaning up?!"