Good Old Sheldon is the second half of episode 7 of season 3 of My Life as a Teenage Robot.
Turns out, poor Sheldon was stuck on the comet aliens' ship when Jenny hurled it into the sun’s orbit (in the previous episode), and he's been spending decades trying to get back to Earth (even though it's only been 24 hours on Earth since he left). Hopefully, Jenny can get him back to his proper age.
- The Gobblin from the McDonaldland commercial makes a cameo appearance.
- Jenny's suit scheme, used to power Nora's age-regressing machine, is a self-reference to TRON.