Bridesmaids and groomsmen/ best man

Sammy 🌷 • Engaged to the love of my life ❤️💑 Gamer 🎮

Sooo me and my man are engaged and we have had conversation about who we are having for our bridesmaids and groomsmen... well he doesn’t want his brother as a groomsmen and i dont want his sister as a bridesmaid and im kinda of scared of people confronting us or being mean about it. I guess my question is that, is it rude to not include siblings as a bridesmaid or groomsmen?