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blood relationship; blood relative
彼は幼い頃に肉親を失い祖母に育てられた。
He lost his blood relatives as a child and was raised by his grandmother.
肉親の情は何よりも深いものである。
The bond between blood relatives is deeper than anything.
戦争で肉親を亡くした人々の悲しみは計り知れない。
The grief of those who lost blood relatives in war is immeasurable.