I actually think in some ways, the time I spent overhearing her interact with coworkers - especially on conference calls where she often used speakerphone, was really helpful to my professional development. I learned all about setting a professional tone, call-muting etiquette, getting people's attention, and voicing disagreements in a professional setting long before I ever stepped into an office.
Doesn't that sort of betray your point that you're "at work" and not "at home?" I'm asking earnestly. I'm about to have twins and I work full-time from home, for the past 3 years and with no intention of going back to an office or to a co-working space.
I am trying now to get all of these sorts of ground rules decided on, and listed out, so that they can be established shortly after the children arrive.
My wife and most of my family already understand the "at work" vs. "at home" distinction and do their best to respect it on the rare occasions that they're around the house during a work day.