Three's Company: My Sister's Keeper

Three's Company: My Sister's Keeper
ABC
October 17, 1978
Sitcom
DVD
B

Franelle Silver joined Wayne & Burditt to write this episode that combines farce with character development.  Janet's college-age sister Jenny (25-year-old Devon Ericson, who had played a young married woman in "The Skating Rink" three years before) visits and sleeps in Jack's room.  When he groggily joins her, Janet of course jumps to the wrong conclusion.  It takes Chrissy's special brand of logic to open Janet's eyes.  DeWitt and Ericson have a nice, believable dynamic as sisters and I wish they'd brought Jenny back, as they did Chrissy's father.  Note that Larry is mentioned a couple times but not seen.