There are a lot of odd security lapses in Amazon’s implementation of Prime Household. Anything that uses Alexa creates shared cards that are visible in the Alexa app. There’s some implicit trust between family members, but even married people may not want to share EVERYTHING. “Echo, add this present for my wife to the list” shows up as a card in your wife’s Alexa app.
We share an Amazon Prime Household with Scott’s dad. We both have Alexa-enabled devices (FireTVs and Dots). Our Dots interact with our home automation system through a Phillips bridge emulator. Scott’s dad has some smart devices, but his FireTV could not find any smart devices when it would search. It would, however, turn the ‘outside lights’ on and off. Except the lights didn’t turn on or off in his house.
Our outside lights started turning on and off one night. We have a lot of home automation, but nothing in the logs indicated why this was occurring. I’m not sure if Scott called him or he called Scott, but we were lucky not to spend a day trying to track down some crazy issue. Evidently your Alexa can switch between profiles on the Amazon Prime Household just by saying “switch accounts”. You can ask it “which account is this?”.
The thing I find odd — our HA Bridge is not publicly addressable. Evidently any device on your account can have another device on your account initiate communication. Otherwise there’s no way a device that is connected to our profile but NOT on our network would be able to communicate with the HA Bridge.