Fictional age regression

Age regression is a popular theme in transformation fiction involving the physical and/or mental reduction in age. This age regression often occurs via magic, including potions or the legendary fountain of youth, or from a science fiction plot device. There are also some characters who are born adults and then age backwards, such as the protagonist of F. Scott Fitzgerald's "The Curious Case of Benjamin Button", the Mork and Mindy character, Mearth, or Merlin in T.H. White's The Once and Future King.

Age regression in many children's series allows for the children to 'take care' of the regressed parents. The children prevent them from doing behaviour that the children themselves were engaged that the parent was scolding the child for, e.g. making messes, doing dangerous things etc. The lesson is the realization that the parents' rules are for the good of the children. Other times the parent was overly harsh or inattentive towards their children, and by being regressed, seeing what childhood is like, and then returned to adulthood, they learn their lesson.

As a kind of offshoot to the age regression genre, many body swap stories (such as the Freaky Friday films) involve an uptight adult and an irresponsible child or teen swapping bodies, with the adult learning to loosen up and have more fun, the child learning that adults lead stressful lives, and both developing a deeper appreciation for the other. There are also many stories where a character is regressed mentally but not physically, so that, for instance, a prim, middle-aged woman will believe she is actually a teenager, and will revert to the wild behavior of her youth. (Both "American Dad" and "Buffy the Vampire Slayer" have done episodes comically playing on this idea.)

A related concept, age progression, obviously involves a character rapidly aging. This is often portrayed as a horrific thing, as a character's youth is stripped away, but it is also sometimes played for comedy (as in Big and 13 Going On 30); in these cases, the story typically concerns a child briefly forced to cope with adulthood and later returning to childhood with a new perspective and confidence. (This element is of course also a typical element of the previously mentioned bodyswap stories, with the swapped child and adult both gaining new perspectives.)