This is my sister. We cover each other's backs. It's a good thing. You don't want either of us to call her sister. And my brother...whoo-doggies! He's got "Sisters"!
We can have sisters by birth or marriage or choice. It doesn't matter what kind of sister you have. You can still have a shirt. Send me an email if you want to order. Even if you don't have a sister, you can make people believe you do.
It's a good thing, indeed.