Keychain Auto-Logout
I suspect Paula’s issues with her Keychains is that they are set to automagically log out after a certain elapsed period of inactivity. Fiddled with those settings on my MacBook, today, and noted that I would hear a little click when the logout occurred and any subsequent activity that required information from the Keychain database required logging back in, sometimes to both the standard “login” keychain as well as, sometimes, the iCloud and System keychains.
Keychain Repair
Another possibility is that her Keychain requires repair: Keychain Access | Keychain First Aid