The contract I'm working on at the moment has optional telework which is where my experience with WFH comes from.

With that being said, there's no effective way to communicate to a four year old that "Daddy is home, but you have to restrict communication with him to only when it's absolutely necessary".

I also find that WFH is made even more challenging if your home has many pending repairs. The temptation to just take a minute to make some progress on e.g., a drywall patch, is hard to overcome when it's right there in front of you.