Google do have these "memories" slide shows which have music in the background. I believe they are AI generated collections (meaning AI has selected and curated the images and turned them into a slide show, not the images themselves are AI generated!!). However, these are in my experience made up of pictures you already have (on your phone/in Google account etc.), not pictures you've never had on your phone. If this is what was generating the slide shows she was seeing, you should be able to find them in the Google Photos app.
EDIT to add: It's possible if she has a computer with Google Backup & Sync or Google Drive installed, and the computer has photos stored on it, these will have been automatically uploaded to Google, hence why they may be showing on the phone even if she hasn't manually added the pictures in question to the phone.
Edited by jonuk76, 01 December 2025 - 03:36 PM.