- Julie Wilson - James Wilson's third wife, an unseen character.
- Wilson's Maid - Wilson's former maid who cleaned House's apartment in Clueless
- Danny Wilson - Wilson's younger brother, an unseen character
- Del Wilson - A cancer patient in the episode Wilson, portrayed by Willie C. Carpenter
- Wilson's disease a disorder caused by the accumulation of copper. One of the diagnoses in The Socratic Method and Remorse.