Advice needed...sister lost her baby.

oohgrrl11

My sister had an ultrasound today, no heartbeat. They also said she was farther along then the 12 weeks they had estimated, closer to 16. She needs to wait until Wed to have the procedure to remove it as it is too large for d&c. I am 33 weeks pregnant myself but will be going with her as her FI is out of state. I'm worried that my big pregnant self will be more of a harsh reminder than a comfort. She lost one 6 months ago and we were due within weeks of each other. I have never lost a baby. What should I do and say? What should I not do and say? So sad....