I'm kind of ashamed to admit that I asked my brother's ex-girlfriend to be one of my bridesmaids.
Will your brother understand that you are inviting his ex-gf?
Yes, I often go with her on holidays and do special things with her like my brother
Are you sure he is okay with that decision. Talk to him first and ask for permission.
I have a feeling that he won't care too much.
I get that you have certain family ties with her. But it would still be good to communicate this with your brother that way that you know that it won't be an issue for your wedding.