To stop sharing photos between two iPhones, you need to turn off iCloud Photos sync in Settings on both devices, as this is usually the cause when using the same Apple ID; go to Settings > [Your Name] > iCloud > Photos and toggle off "Sync this [Device]," then potentially delete synced photos from iCloud.com on one device if needed, and consider separate Apple IDs or Family Sharing for better privacy, according to Reddit and Quora users and Quora users.
Why are my photos being shared with another iPhone?
``iCloud Shared Photos Library'' is a function to share libraries between multiple iCloud accounts. What you are experiencing is that both your and your partner's photos are being stored in iCloud and now merging because you are both using just one Apple account.
Why are my photos showing up on my husband's iPhone?
Using the same Apple ID, Google account, or cloud storage service can make your husband's phone look linked to yours. Other things that can create the same effect include shared albums, file-sharing features, location sharing, or third-party apps that sync across devices.
How do I turn off automatic photo sharing on my iPhone?
On your iPhone or iPad, go to the Settings app > Apps > Messages > Shared with You, then turn off Automatic Sharing or turn off Shared with You for a specific app.
Disabling iCloud Drive will stop syncing files to your device, potentially freeing up storage space. However, keep in mind that any files already synced to your device will remain unless you choose to delete them.
iOS devices can share photos and videos with each other using the iCloud Photo Library of the same iCloud account. This feature may sometimes cause data loss and storage issues.
