Turns out, this has an interesting side-effect. Google binds calendars to a user name, so there's a calendar for emily@our_family_domain in Google Apps. So, you might wonder, what happens if you go to calendar.google.com when logged in to the standard Google Account with the Google Apps email?
Then you find your Null calendar ...
Get thee to the null calendar!
Google struggles with their Google Apps/Google Account dichotomies.
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