Ancestry.com

I was adopted as a baby back in 1970. After decades of not particularly caring who my biological parents, I finally got my original birth certificate last year. Too late unfortunately. But I've gotten to know two half-sisters who've been both really nice and nothing at all like me. The older one was born in 1983, they're both way more outgoing and sporty (they grew up in Hawaii and surf) and our looks are completely different.

They say reunion is a roller coaster ride emotionally and it has been. A lot of guilt on my part, a feeling of betraying my parents (even though they encouraged me to do the search.) But it's been good as well, finding out that my birth mother was a much-loved woman and extraordinarily normal. But they also say that things calm down after a year or two as well, so hopefully that should happen with your sister.