Bruce Wayne, Jr. was the younger son of Bruce Wayne and Selina Kyle, and brother of Thomas, in an illusion where Bruce's parents never died. (Batman: Gotham Adventures Vol 1 #33)
Instead of becoming Batman, Bruce led a sheltered childhood in Europe. He was married to reformed cat burglar Selina Kyle and had children. Against his father's wishes, he took his family back to live in America. Arriving in a hellish Gotham, he mused that someone should do something about it.