Disowned sister in law

So my sister in law who is in her early twenties got pregnant out of wedlock by a black guy. My mother in law kicked her out of the house when she told them. My mother in law is very racist, I've tried to talk to her and have her see the light about black people being no better or worse than whites but she doesn't listen. And to be honest I've never talked to her about my sister in law because it's such a touchy subject.

Anyway, I just gave birth last week and after the baby and I came home (to a doting grandmother) my husband (who does not talk to his sister either, not because of the boyfriend but because of her decisions in general) shows me a text from his cousin telling him his sister had the baby a few days after I did.

I asked him if he told his parents or if they knew at all. He just shrugged. I asked him if he will tell them. He said no. He didn't even seem to care!

I don't understand this family!! They don't talk to one another. They always claim to love one another and "blood is thicker than water" and all that bs but then when one "offends" it's like shut the door and literally change the locks!!

What pisses me off most is my brother in law passed away five years ago and they practically worship him now. My husband always talks about how you have to love family now because they could be gone tomorrow and yet he ignores his sister! My mother in law is completely in love with my baby and it bothers me she won't show the same love to her daughter's child.

I really want them to know she had the baby but I don't feel it's my place. I want my husband to tell them and I want so badly for them to go see the baby too... I just don't know what to do.