An adorable 7-year-old Joseph Gordon-Levitt got one his very first roles on this classic ‘80s sitcom.
Joseph Gordon-Levitt
When did he first appear: "Sign of the Times"
Who did he play: Dougie, a kindergarten friend of Andrew.
Where you recognize him from (obviously): 3rd Rock from the Sun, (500) Days of Summer, Inception, and 10 Things I Hate About You.
River Phoenix
When did he first appear: "My Tutor"
Who did he play: Eugene Forbes, a 14-year-old math genius who develops a crush on Jennifer after coming to tutor Alex.
Where you remember him from: Stand by Me, Indiana Jones and the Last Crusade, and My Own Private Idaho.
Christina Applegate
When did she first appear: "Band on the Run"
Who did she play: Kitten, a member of Jennifer's band.
Where you recognize her from (obviously): Don't Tell Mom the Babysitter's Dead, Anchorman, The Sweetest Thing, and Married... with Children.
David Faustino
When did he first appear: "To Snatch a Keith"
Who did he play: Keith Bailey, the son of a divorced family friend who was taken away from his mother by his father.
Where you recognize him from: Married... with Children