Wife's iPhone asking for MY login

Sounds like perhaps an app was installed from your account (perhaps through a sync of some sort or by logging in as your account at some point).

 

That happened to me too once. That specific app was installed from your account. It should ask for her login for the rest of the apps that were installed normally from her own Account.

 

Yeah the app is somehow associated with your account. Maybe from home sharing or something?

 

Most likely one of those Apps has been downloaded using your account back in the day. I would recommend deleting the App and re-download it with her own account, unless it costs money you want avoid spending then i suggest to just update it using your credentials

 

x2. Had to do this for my wife. Otherwise it will never update without your signing in.

 

update each app in the list one by one. It will ask you instead of updating. All others will update.