For example, are you referring to:
* Will Smith? He is an actor and musician, but there's no mention of him having a father who was in a band.
* A character named Will? If you're talking about a character from a book, movie, or TV show, please specify which one.
* Someone named Will who you know? If you're referring to a real person, I need more information about them.
Once you clarify who "Will" is, I can try to help you find out about his father's band.