His sister Natasha appeared as an assistant during the Judges Retreats round.

Entity and relation annotations:
id: 0
type: entity
value: text: Natasha
labels: <Person>
id: 1
type: entity
value: text: the Judges Retreats round
labels: <Event>
id: 2
type: entity
value: text: assistant
labels: <Title>
type: relation
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labels: Person:participates_in:Event
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type: relation
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labels: Person:holds_title:Title
from_id: 0