I'm not sure what you mean by synchronized account, but normally each account will need to set up notifications for themselves. The way that I recommend, so that you are notified of all changes on the board is to "watch" the board which you can activate by going to "Show Menu > More > Watch".
If you continue to run in to issues, it would be great if your wife could write in to our Support team at trello.com/contact.
Hello Community! My name is Brittany Joiner and I am a Trello enthusiast and Atlassian Community Leader. I'll be sharing with you a series of videos with my top tips on how to best use Trello...
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