The Brave Yong Sujeong: 1x4

Episode 4

Together with his son who was born soon, the two hats were left to Monk Cheonjin (played by Kim Chu-wol). Afterwards, the boy grew up to be a Yeo-ju (played by Seo Joon-young) and appeared in a reliable military uniform. Yong-jong stopped by the store to change the helmet that fell off. He tried on a new helmet, but it didn’t come off.