Adding new bones to a character

Questions & Answers
1

I have several characters that need to be updated with a few new bones. (for eye movement) If I try to simply add these new bones in Blender, unity will not add the bones to the scene hierarchy, and the character model will break.

What is the correct way to add bones to an existing character in the scene?

2

I’d go out and say it: It’s not possible without breaking the model. You have to go back to Blender, add the bones to the skeleton, then re-skin the character, and then re-export it. That might very well mean having to re-do all envelopes and weights again.