Please help...

Im 27 weeks and 4 days, my sister found out she is also 6 weeks pregnant on my 20th week. We went to child birth classses together, set up our registries together. We were both so excited, she found out recently she was having twins! Very exciting, until 2 days ago she lost her babies because of her endodemitriosis. She is 26 and im 22, we are extremely close and i feel like i dont know what to say to say to her