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It's not your blood they needed. It was my father's blood. My blood... the blood of a pirate.
— Will Turner ‧ Pirates of the Caribbean: The Curse of the Black Pearl

Behind the line May contain spoilers.
Our reading
An editorial interpretation.
The speaker corrects whose blood was needed, connecting their own blood with their father’s and identifying it as a pirate’s. The repeated references turn the statement into a recognition of inherited identity. What matters is a family connection that makes this person relevant to the demand.
Context reviewed