brandnewworld Said:
"My husband passed away and I am looking for information on how to save all the content in his aging iPhone and iPad devices on my MacBook - managing dual IDs so that I can access the data without having to buy new devices to restore the data to. Is this possible?"
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You should add his account info your account. All would sync.
Managing a Deceased Family Member's Device:
Transfer Ownership:
- Transfer ownership of your husbands Apple Account to your account.* If his device were synced with iCloud, then you may be able to get it from is iCloud Drive, rather than directly from a device.
- Contact Apple Support, seeing if you can get the info.
* Go Here: How to Request Access to a Deceased Family Member's Apple Account - Apple Supporte