Officially adopting my sister's child, I'm freaking out.

I'm not sure if this is the right place for this question, but I am totally beside myself and any advice would be appreciated.To make a long story very short, my husband and I have two great kids of our own a boy and a girl (she's 3 he's 6) recently we learned devastating news that my sister (who has long had drug and alcohol problems) has cirrhosis of the liver and will likely pass soon ( as she is being denied a transplant). She has one son who is five and is currently staying with his father's mother. His father passed away a few years ago also from drug-related issues. The situation is a total mess and I can't believe it has come to this.We've lived in the same city as my sister and although we've never really gotten along (because of her mental issues and addiction) our kids have grown up regularly seeing their cousin. We love him so much and will want to adopt him when his mother passes. His fathers family is unfit to care for him and I want him to be able to grow up with my children.My questions are many but I wanted to see what you all think.My husband and I are white but my nephew is biracial ( black and white) I hate to admit this, but raising a black child is something that gives me anxiety because of how he may feel out of place, I want the world for him and while I know my children will love him I fear we will be judged in public by people who don't know the full story.Would my children call him their cousin or brother? since when the adoption goes through, we would be his parents and not his aunt/ uncle anymore.Has anyone done an intra-family adoption before that can speak on this? We have the legal bit worked out, but I need some advice on how to transition my kids for this.Sorry for the rambling, gives you some insight into my current state of mind, haha. Any advice would be appreciated. via /r/Parenting https://ift.tt/2HKQJHM