You've done the right thing by just being there for her. I've been there myself and know what upset me even more. The biggest thing was everyone telling me it happened for a reason. I knew that and didn't need reminding.
Also, my family called me everyday, I didn't want that because I just wanted to be alone and didn't want to be bothered. I know everyone is different, but I would ask what she would like from you.
My sis in law was due a month before me and although it was upsetting that she was still pregnant, I never expected her to not talk about her pregnancy or baby. Both you and your sister are equally important just as much as the fact that she lost her baby and you are still pregnant. Yes, give her some time to heal and then have a talk about your pregnancy. Perhaps you could ask her to get involed somehow and maybe organize a memorial for her baby. We planted a tree and some flowers and bought a beautiful baby cross and I just finished a memory album from my doctor's apts and ultrasounds.
She will heal with time, but will never forget or truly get past this. I lost my baby at 10+2 back on Aug 4, 2006 and I still think of our Morgan. I'm currently pregnant again and we plan on using Morgan for the middle name in honour of our baby.
Let her cry, scream, get angry and just hold her. Your sister, you and your family are in my heart and prayers and I'm so sorry for your loss.
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