18 Feb English (Midlands UK). Yes. Half-brother = same father, different mother (or vice versa). Stepbrother = son (from a previous marriage) of a step-father or step- mother and for completeness: Brother-in-law = sister's husband or wife's brother . Unfortunately, French only has one word beau-frère for the last two. stepbrother - traduction anglais-français. Forums pour discuter de stepbrother, voir ses formes composées, des exemples et poser vos questions. Gratuit. stepbrother• I have five and a half stepbrothers and sisters.• Shari struggles against her passionate feelings for her stepbrother.• Was it possible her friend had been matchmaking - her stepbrother and her best friend?• Caro said her stepbrother was Robert Marsh the naturalist.• Your son resents his stepbrother for taking up.