This occurs for me after using Animal Friendship Scroll for Advantage on a die roll for story interaction. I have been able to repeat this consistently.
1. Interact with Owl Bear or Scratch (Dog) with dead owner nearby (either one will work and so will any other dialog using Animal Friendship scroll)
2. In the dialog when you have to complete a die roll use Animal Friendship scroll for advantage.
3. Complete the story dialog sequence.
4. Create a new save or attempt to overwrite an old save, the game will crash.
Note also that anytime afer using the Animal Friendship scroll, even an hour after using it and trying to save will crash the game.