Siobhan and her twin sister, Bridget
, were born on September 30, 1979, to unnamed parents. 6 years prior to the show and before Siobhan married Andrew, the sisters had a falling-out over an accident involving a boy named Sean
. Siobhan later married Andrew, but began having a affair with Henry Butler
, who is the husband of her best friend, Gemma
Her known location is Paris, France. She also appears to be working with someone, who provides her with information about Bridget.
At the end of 'If You Ever Want a French Lesson
', she finds out that she's pregnant.
In 'Oh Gawd, There’s Two Of Them?
', it is revealed that the man who she's been on the phone with was Charlie Young
. In 'That’s What You Get For Trying To Kill Me
', she came to New York and killedCharlie
after he killed Gemma
,who he had kidnapped.
In the episode Whores Don't Make That Much
, we learn that 7 years ago before she met Andrew in New York, she was living in Oklahoma with ex-boyfriend/husband Dylan. We also learned that Siobhan had a son named Sean, who we also learned about in Pilot
episode but we didn't know about who he was or why Siobhan had a picture of him in her room.