black sheep
US /blæk ʃiːp/
UK /blæk ʃiːp/

1.
le mouton noir
a member of a family or group who is regarded as a disgrace to them
:
•
He was always considered the black sheep of the family because of his unconventional lifestyle.
Il a toujours été considéré comme le mouton noir de la famille en raison de son mode de vie non conventionnel.
•
Every organization has its black sheep, but we try to support everyone.
Chaque organisation a son mouton noir, mais nous essayons de soutenir tout le monde.