An experiment that regresses people into babies activates and turns Stitch, Nani, Jumba, Pleakley and Gantu into infants, forcing Lilo and Reuben to babysit them. When Babyfier gets loose, Baby Stitch and Baby Gantu battle for the experiment, while Baby Pleakley and Baby Jumba (who still possesses the intellect of adult Jumba) have to mix an antidote for the age regression, requiring adult coffee in the remedy. In the end, Stitch unleashes it and everything goes back to normal (save Gantu, who remains a baby for now). Meanwhile, Babyfier is given a job at the dog pound turning old dogs into more adoptable puppies.
- Moral: Everyone has hardships and problems in their lives, no matter what age.
- It is hinted that Mrs. Edmonds may know a little about the illegal genetic experiments when she acknowledges Lilo's desire to turn Babyfier good, though it could have been just a lucky guess.
- Nani never found out that Lilo and Stitch were not trying to sneak off to see Sludge Mummies by themselves.
- As babies, Nani and Jumba are voiced by Grey Griffin and Jason Marsden respectively.
- Although Stitch was not born as a baby (being a genetic experiment), Babyfier was still able to turn him into an infant.
- It is unknown how Lilo and Reuben were able to find/borrow strollers for their infantile members.
- Baby Gantu has a blue stroller, but it later appears green.
- Some people who are turned into babies reappear in their adult forms before Jumba has found the antidote.
- The tourists in front of the hotel change in each scene.
- The baby forms of the characters in this episode were also used in the Disney Baby merchandise line.
- In spring 2004, Disney Channel held an online poll that asked viewers for their favorite experiments and episodes from Season 1 of the series. According to the top 10 results of that poll, "Babyfier" was the #2 most popular episode and experiment, just behind Angel and her episode.