Wow, this would be a LONG message if I did the whole background but here is the very abbreviated version.
Yes, Sami is the Daughter of Marlena and Roman Brady, however....
Sami has been married to EJ Dimera, and is now engaged to him again. Sami has 4 children at the moment. WIll Horton (father Lucas), Twins, Ali and Johnny (Ali's father is Lucas and Jonny's father is EJ....yes, twins with different dads) and a baby, Sydney (father is EJ).
Not sure if you stopped watching before EJ came on the show, but he is yet another one of Stephano's children, though he first appeared with the Name EJ Wells. (Mother is Susan Banks)
Right now, Sami has been living in the Dimera mansion and has JUST gotten engaged to EJ, though aparently, they are going to break up within the next month because Sami will find out that EJ was the one behind the kidnapping of their daughter Sydney b/c he wanted to get back at her for hiding her pregnancy by entering the witness protection program. (She fell in love with the agent protecting her, Rafe, and he is now part of the Sami, EJ love triangle).
I used to love to old Sami that was really rebellious, now they have turned her character into a whiner. I think that pairing her with EJ would allow her to show her devious side again.
If you want the longer story, I would go to
http://daysofourlives.about.com/od/c...a/EJDiMera.htm
and read up on it!
Glad to hear of another DOOL fan on here!