Justin Richardson, MD, is the coauthor, with Peter Parnell, of the award-winning picture book 
And Tango Makes Three. Dr. Richardson is an assistant professor of psychiatry at Columbia and Cornell and the coauthor of 
Everything You Never Wanted Your Kids to Know About Sex (But Were Afraid They'd Ask). Dr. Richardson and his advice have been featured in 
The New York Times and 
The Washington Post, on the 
Today show and NPR's 
Morning Edition, and in numerous magazines. Dr. Richardson lectures to parents and teachers on parenting and the sexual development of children. 
Peter Parnell is the coauthor, with Justin Richardson, of 
And Tango Makes Three. He is a playwright whose plays have been produced at the Public Theater and Playwrights Horizons in New York City, the Mark Taper Forum in Los Angeles, and the Seattle Repertory Company, among others. His play 
QED was produced on Broadway. He has written extensively for television as a producer for both 
The West Wing and 
The Guardian; he has also written episodes of Maurice Sendak's series 
Little Bear. He lives in New York City. 
Henry Cole has written and illustrated more than 150 books for children, including
 Spot, the Cat; 
And Tango Makes Three; 
Oink?; and 
Little Bo in France. He is also the illustrator of 
With a Little Help from My Friends by John Lennon and Paul McCartney. A former elementary school teacher, he now writes and paints full time.