Susan and Gordon's adoption of Miles in 1985 (beginning with Episode 2122) was a major event on the show. Subsequent episodes dealt with the infant Miles' adjustment to his new family, and he would gradually become one of the familiar kids on the street. Miles' birthday is December 4th.
As a teenager, Miles formed his own band. In Episode 4112, he graduated high school alongside Gabi (despite the fact that the characters' respective births on the show occurred four years apart). A flashback in this episode shows that Miles was shy on his first day of kindergarten.