My big sisters pregnant but her other child has swine flu?.?

My neice is 11 years old and my sister is 32. shes 8 months preg, Is she at risk? I want to take my neice home with me to protect the unborn baby would this be a good idea? Im really worried right now what happens if my sister and her baby catch swine flu? She wont get the jab for it, she does not think tammiflu is safe! Shes not over keen on having to stay away from her daugher either, I think she needs to protect the weakst member of her family now. I am at a loss of what to do. Im just her younger sister but i am really worried. I dont mind keeping my neice, even if it meens my and my son catch swine flu. Just as long as the little baby does not get it.