He has a younger brother, "Little Unrestrained" Mu Chun.

Entity and relation annotations:
id: 0
type: entity
value: text: Mu Chun
labels: <Person>
id: 1
type: entity
value: text: "Little Unrestrained"
labels: <Title>
type: relation
to_id: 1
labels: Person:holds_title:Title
from_id: 0