My little sister told me something insanely bad and i dont know what to do.?

I disagree with Powder. I do agree that it's important that your parents know if she is really pregnant, but your younger sister should be the one to tell them. You should encourage your sister to tell your parents, and you can be there for her to give courage and support. She and your folks will need it. Her life doesn't have to be over. She should consider adoption. There are many couples willing and waiting to give that child a good and loving home.