As fantasy sitcoms go, this one was a few years too late to find an audience.
In fact, one critic dismissed Jennifer Slept Here as a cheap knockoff of Topper, except that the titular ghost (Ann Jillian) was an actress who was killed when she was run over by, of all things, an ice cream truck. Time passes, and Jennifer's lawyer and his family move into Jennifer's old home in LA.
Jennifer bonds with the lawyer's teenage son (Glenn Scarpelli, ex-One Day at a Time), and there were hints that she was more than just the kid's ghostly guardian. Unfortunately, the series initially aired on Fridays, and was thumped in the ratings by Dukes of Hazzard. Enough said there, but NBC tried it out as a summer replacement on Wednesdays to recoup production costs. While the ratings were better, it wasn't enough to save the show.
After the series, Ann Jillian, who co-wrote the show's theme song, sung by Joey Scarbury (Greatest American Hero), revealed she had breast cancer. That would spark interest in her earlier series, It's a Living, such that it would be revived a couple of years later, though Jillian would only appear during the first year of the revival.
Gilmore Box provides the open to Jennifer Slept Here.