David Jacob "D.J." Conner is the boisterous first son of the Conner household on the TV series "Roseanne". The part of D.J. on the series was played by then-child actor Michael Fishman. The 3rd child of the Conner family and was the youngest before his little brother, Jerry Garcia, was born. D.J. is the most gullible, naive, and foolish of all the Conner kids.

D.J. tended to be indulged more by Roseanne and Dan, partly because he would not get into serious situations as much as his older sisters and had a less argumentative personality; however, he is nonetheless a very mischievous child, and well-versed in the art of blackmail.  This is sometimes tolerated by his parents, who like to preserve his innocence when their lives become difficult, but not by his sisters, who are shown to (for the most part) despise him.

Becky would often babysit her little brother and indulged him somewhat in early seasons, but she saw him more as a distraction and a nuisance, a belief that his actions did little to counter.  After she eloped with Mark, there was little connection between her and D.J., although he greeted her happily the first time she came back.  Darlene, on the other hand, would retaliate physically when D.J. pulled some trick on her or otherwise irritated her. Despite being intimidated by his middle sister, D.J. continued his attempts to annoy her for most of the series.  However, when he visited her at college, he honestly told her that he missed her.

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