Ngao was the second son of Chao Anouvong.

Entity and relation annotations:
id: 0
type: entity
value: text: Ngao 
labels: <Person>
id: 1
type: entity
value: text: Chao Anouvong
labels: <Person>
type: relation
to_id: 1
labels: Person:family:Person
from_id: 0