From Dipper, the celestial dolphin; to Alice and Jewel, the pink-skinned twins; to Jim Scott, the invisible man in the moon, children’s imaginary friends come in innumerable shapes and sizes.

Categorizing these creations—while also trying to glean information about the mindset and personalities of their youthful creators—can be a daunting task for developmental psychologists.

Over the last two decades, researchers have pieced together unexpectedly diverse and nuanced profiles of the children who create imaginary companions. In the first episode of Science Friday’s The Real Guide to Imaginary Companions, developmental psychologists Marjorie Taylor and Tracy Gleason describe how scientists study this playful phenomenon in order to understand the types of kids who have imaginary friends, why they create them, and what role these pretend pals play in childhood development.

Credits Produced by Science Friday with generous support from the John Templeton Foundation

Produced, directed, and narrated by Luke Groskin

Filmed by Katie Graham, Luke Groskin and Patrick Pelham

Edited by Erika Sutter

Animations by Gabe Darling and Candice Aquino

Music by Audio Network

“Alice and Jewel” voiced by Annie Nero

Additional Footage by

The Shining Footage ©Warner Brothers, Inc. 1980

Calvin and Hobbes by Bill Watterson

Angry Boy, Affiliated Film Producers

Special Thanks to Danielle Dana, Jennifer Fenwick, Becky Geer, Tracy Gleason, Elizabeth Delucia Landon, Alex Riviello, Jenny Shalant, Christian Skotte, Marjorie Taylor, and Jacqueline Woolley.