Once again this season David and Donna are reminiscing about something that didn't happen. According to them they started dating when Mel (David's father) was courting Jackie (Kelly's mother) which they say was in april five years ago. That's inaccurate. Mel and Jackie started dating in the summer episodes of 1991 and at that point David and Donna had barely become friends. They went on their first date in episode 17 of season 2 (Chuckie's Back) long after Mel and Jackie had become a couple.