HA! DJ - David
I know DJ stands for David Jakob , but they never really reveal that but only in 3 episodes ( I think )
1. We not in Kansas anymore
2. Chicken hearts - Roseanne putting vacuum in closet after cleaning for Brian's visit and DJ is hiding in closet and she says " David Jakob I see you "
3. In episode when Roseanne had her birthday and Dan build her writing room downstairs - after they had cake Roseanne asked kids to clean up and Darlene said to DJ -" David you have to help "