'sibling'はこちらの項目にも見つかりました。
英語の見出し語に対する説明:
baby sister
- big
- big brother
- big sister
- blood brother
- brother
- brother-in-law
- eldest
- foster sister
- fratricide
- grandnephew
- grandniece
- half blood
- half brother
- half sister
- half-blooded
- identical twin
- kid brother
- kid sister
- little
- little brother
- little sister
- nephew
- niece
- older
- Siamese twin
- sister
- sister-in-law
- twin
- twin brother
- twin sister
- younger
- younger sister
- youngest