Both of his grandfathers had served in the Confederate Army during the Civil War.

Entity and relation annotations:
id: 0
type: entity
value: text: the Confederate Army
labels: <Organization>
id: 1
type: entity
value: text: during the Civil War
labels: <Date>
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type: entity
value: text: the Civil War
labels: <Event>
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labels: Organization:Engagement:Event
from_id: 0