sister

(8)“brother” and “sister” mean one who at the time of the death of the employee is under 18 years of age or over that age and incapable of self-support, and include stepbrothers and stepsisters, half brothers and half sisters, and brothers and sisters by adoption, but do not include married brothers or married sisters;

Source

5 USC § 8101(8)


Scoping language

For the purpose of this subchapter
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