brother

(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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