|Family|| Sharon Marsden (mother)|
Joseph Hollister (father; deceased)
Olivia Benson (paternal half-sister)
Tracy Harrison (fiancée)
Ty Mardsen (step-son)
Olivia Mardsen (daughter)
|Last Appearance||"Child's Welfare"|
Simon Marsden (born March 24 1973) is the younger half-brother of Olivia Benson.
He had a girlfriend named Tracy who had a child through a previous relationship. Simon has a daughter named Olivia Marsden (Born 2011) and a stepson named Ty (born 2007) through his fiancé Tracey. Simon was a prime suspect in a rape case and was framed by Captain Julia Millfield, who was convinced he had raped her sister on a date. On that night, all that had happened was he kissed her and she freaked out because of her molestation from her father. Simon's father raped Serena Benson. His half-sister Olivia Benson found him because she ran her DNA through kinship analysis.