Bravery and persecution. Sookan shows a ton of bravery and perseverance throughout the entire book because of the following reasons.
Sookan shows bravery because she always protects her little brother throughout the entire book.
She protected her brother whenever Captain Narita came through and protected him when the Russians came into their house and stole their stuff.
"The young soldier lifted Inchun up, twirled him in midair, and laughed. I screamed. I was afraid they were going to hurt him." Nuil choi 101
She shows perseverance because when escaping the country she scraped her feet and kept walking, also carrying Inchun on her back while he was sleeping, which is hard to carry a sleeping child. For example, when she was escaping the country