Originally published in Korean language as A Happy Hat copyright (c) EenBook Co., 2011.
Cecil Kim studied child psychology in her undergraduate and post-graduate studies. She has worked in psychological treatment for children and is currently reaching out to more children and their hopes and dreams through picture books. Her other works include Crybaby Cloud; Embarrassment, Go Away; and Let's Wash Hands First. Joo-Kyung Kim studied design at university and is now working as a children's book illustrator. She was a runner-up in the 15th and 16th Noma International Concours for Picture Book Illustration. Kim continues to work hard writing and illustrating so that children can enjoy more fun and entertaining stories. Among her other published works are Red Goblin, Tell Me About Cells; Star Family Takes Off on a Journey of the Solar System; and The Three Musketeers of Goguryo Pyungyang-Sung.