Plot hole: The Winslows' younger daughter, Judy, disappeared from the show in 1993 (halfway through the series' run) with no explanation.
Hot Wheels - S4-E12
Continuity mistake: Laura meets a guy named Ted supposedly for the first time. He is selling candy bars around the neighborhood and happens to knock on the Winslow family's door. Laura goes out on a date with him. However, Ted and Laura have already had several interactions, and have already dated and broken up in previous episodes in season 4.
Suggested correction: This is because the episodes were aired out of order. "Hot Wheels" was the 2nd episode produced for season 4 (production code 447802) and aired following the 15th and 13th produced episodes.