Barbara Knorr was a human child.
From 1932 to 1940, many children, including Barbara Knorr, went missing in the United States. They were kidnapped by Odd Bob the clown. The kidnappings were documented in an article by Francis Lincoln.
Her mother Elizabeth Knorr made a plea that everyone who knew information about Barbara's whereabouts should get in contact with her. (TV: The Day of the Clown)