See if you can recover the ID/password. Try all the email addresses you can remember.
Apple ID - How to find your Apple An iCloud e-mail address is an Apple ID.
Apple ID - Find
For the Apple ID password, enter the Apple (iCloud) ID and click Forgot Password.
Apple ID - Manage
Apple ID – Forgot Password
If necessary, if you/she are the original owner, contact Apple. Apple can remove the Activation Lock if provided the required paperwork. Either take the device, the original purchase receipt with the serial number, and a photo ID to the nearest Apple Store (if it has reopened)
Genius Bar Reservation and Apple Support Options - Apple.
or contact Apple ID Support.
Apple ID - Official Apple Support.
Contact Apple for help with Apple ID account security - Apple Support. (Link doesn’t always load)
Get Support Work through the screens to get a chat option.
Apple Support schedule phone call
https://twitter.com/AppleSupport People have posted it may take an hour or more to get a response.