[K-Story] The sun and the moon (English)

In a mountain village, young children - an older brother and a younger sister - have been waiting for their mother all day. When it gets dark outside, someone finally knocks on the door. “Children, open the door. It’s me, your mother.” The children should be happy, but the older brother stops his sister from opening the door. What is going on? Who is knocking at the door? Let’s go find out at the mountain village.