First appearance of Olivia's long lost half brother Simon Marsden, played by Michael Weston.
It's not illegal for a person to test their own DNA to look for potential genetic relatives, it is done all the time. In fact there are companies that provide this service to people who send in a sample of their DNA to learn about their ancestry and find any potential living unknown relatives.
When Olivia and Simon are talking about their childhoods, Simon asked if she preferred Dukes of Hazzard or Little House on the Prairie; she responds "Dukes". Michael Weston, Simon, was in the 2005 movie, Dukes of Hazzard.
It is revealed that Benson's father died ten years ago.
Olivia mentions her mother, Serena Benson, died. She had found out about her mother's death in the episode Taken (2000).