* Children's Literature: The phrase may have been popularized by children's books and stories of the time. For example, the book "The Little Duck" (1916) by L. Frank Baum, author of "The Wizard of Oz," features a character named Ducky.
* Duck-themed Products: The popularity of ducks in children's toys and products, such as rubber duckies, during that period may have contributed to the phrase's use.
* A Slang Expression: "Just Ducky" may have started as a slang expression for something good, possibly based on the idea that ducks are cute and harmless.
Regardless of its exact origin, "Just Ducky" became a common expression in the 1920s and 1930s, meaning something was good or satisfactory. It was often used in a lighthearted and playful way.
Interestingly, "Just Ducky" has lost some of its popularity in modern usage. While it's still understood, it's not as common as it once was, possibly due to its association with a bygone era.