Im pregnant my sister lost hers

So at the beginning of the year my sister announced after 10 yrs ttc she was pregnant. She has grown stepkids but none of her own. But she ended up miscarrying. Then surprise without even trying im pregnant again. Its hard because i feel like im betraying her if im happy about the baby. Its mine and my husbands first together. So we were excited. But i know she is hurt. I know i did nothing wrong. I don't discuss anything baby related around her out of respect. Idk how to approach this. We use to be really close but over the last 2 years we have drifted apart. She is my only sibling. And i dont want to hurt her. But i feel like my family should still be allowed our happiness. Idk what to do. Suggestions?