who is the round character

Most of the characters are round. I might consider Grandmother ("Poh-Poh", or "the Old One"). Grandmother is the matriarch of the Chen family. After a difficult life in China, she immigrates to Canada where she lives with Father and Stepmother, helping to care for the children. Grandmother is very close with Sek-Lung in particular. Grandmother is clever, resilient, and creative, but she is also traditional and resistant to change. She dies in the autumn of 1940, at age 84.