Who is bio dad on young and restless?

The term "bio dad" usually refers to a biological father. In the context of "The Young and the Restless," it's a bit unclear who you're asking about.

Could you please specify which character's biological father you're interested in?

For example:

* "Who is Billy Abbott's bio dad?"

* "Who is Adam Newman's bio dad?"

Once you provide more details, I can give you a more precise answer!