Managing multiple Apple IDs

About a year ago, my wife and I have moved from sharing an Apple ID to managing our own separate accounts. We still share content via Apple One and enabling certain services from our respective accounts on our devices, including sharing calendars etc. In the past few days we've run into a weird situation where our profile pictures get swapped between accounts -- my profile ends up in her System Preferences main pane and vice versa. It's the same with the image that can be edited in Systems Preferences/Users and Groups. This behavior did not begin (or I didn't notice) until the other day when I actually started editing/changing these images for this first time. It's weird...grateful for any info to fix this, as well as any "best practices" for managing separate Apple IDs when there is lots of sharing between them. Thanks.