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.

Amy June Bates has illustrated books including the Sam the Man series, Sweet Dreams and That’s What I’d Do, both by singer-songwriter Jewel; and Waiting for the Magic by Patricia MacLachlan.

She lives in Carlisle, Pennsylvania, with her husband and three children.