How do I restore my dead wife's ipad? I was using it after she died but it tried to upgrade itself and now it is asking for an apple ID and password. What can I do to restore it so I don't have to toss it and get a new tablet?

I have my deceased wife's ipad. While trying to upload some photos off from it to my MAC it decided to update itself. It is in activation lock and asking for her apple ID and a password. Now I may know the password but I don't have a clue what her apple ID might have been.. What can I do to get past this and restore the ipad for my use?