Half-brother or step-brother
I am working on the updated French family lesson. Is there a way to differentiate between a half-brother (a brother who shares one birth parent with you) and a step brother (a brother who is not related to you by blood, but the child of one's step-parent). I have looked but not seen a way of differentiating.
"Beau frère" is the brother of the person you marry.
My Robert & Colins English-French/French-English dictionary mentions: "stepbrother = demi-frère" - "beau-frère = brother-in-law" ( my additional comment for beau-frère: this can be either, as JBEsip mentions, the brother of the person you marry, or it can also be the husband of your sister)
It was the online version of the Collins dictionary that I checked. Thanks for the correction. I think in English brother-in-law can be the brother of the person you marry, the husband of your sister, or the husband of your spouse's sister.