A natural leader, an undercover geek and her father's baby, Silvia grew up studying medicine but ended up in the force, supporting her father with forensics and undercover investigations at the San Antonio Precinct. While she has been successful in her career, her lovelife has been catastrophic. Her first kiss (with her sister-in-law Pepa) caused a scandal and resulted in Pepa being expelled from the family. Her first marriage, to family friend Lucas, ended in less than a year. An office romance with partner Montoya ended in disaster when she became pregnant with his baby, and then lost it when she was shot in the stomach.
Pepa unexpectedly falling back into her life sent Silvia into a tailspin. Silvia was immediately drawn to her, and old feelings reemerged as Silvia's sexual identity crumbled in the face of her attraction to her brunette sister-in-law. Though she was at first confused and frightened, she was unable to deny her feelings for Pepa, and pursued a romance with her. Silvia found herself truly in love for the first time, much to the dismay of her father. However, he learned to accept her relationship with Pepa, and gave them his blessing. Silvia found the courage to allow herself to be open about her relationship to Pepa, both to her family and to her co-workers at the precinct.
After a year with Pepa, Silvia was more happy and in love than ever, and secure enough in her relationship with Pepa to want a child with her girlfriend. She was however, unable to have children, thanks to having her uterus removed when she lost her first baby. When Pepa drunkenly agreed to a baby, Silvia's excitement overwhelmed her, and she completely missed the obvious cues that Pepa was not quite ready for a baby. When she began to immediately make plans to inseminate Pepa, Pepa panicked, and Silvia was blind-sided and horrified when she heard Pepa ranting to her brother over a police tap that she was drunk when she promised Silvia a baby and she didn't want the baby. Heart broken, and dreams dashed, Silvia closed herself off from Pepa. When Pepa tried to speak to her the next day to tell her she had changed her mind, Silvia was unable to take it and slapped her. When Pepa instinctively slapped back, Silvia attacked her.
Immeasurably hurt by Pepa's betrayel, and grieving for her lost child all over again, Silvia let her anger consume her, but found her love for Pepa devestating her completely when Sara revealed that Pepa had a plan to sleep with a past lover in order to impregnate herself and give her a baby. Silvia found Pepa and broke up with her, reminding Pepa how she had run away from her family before and telling her she was the last person she would have a family with.
Though to Pepa, her demeanor was angry, Silvia was clearly destroyed over losing the love of her life. She changed the locks and kicked Pepa out of the apartment, and once alone, got high on a marijuana joint and took a box of Pepa's things to Sara's house. Once there, she broke down in tears, unaware that Sara had invited Pepa to live with her. When Pepa showed up, she tried to leave, but Sara forced her to stay so she and Pepa could talk things out.
When Pepa admitted to Silvia that she had been afraid, just as Silvia had been afraid countless times before, Silvia began to understand Pepa's position. When Pepa asked her if she would really leave her for the only moment of fear that Pepa had ever had, Silvia tearfully shook her head no and joyfully reunited with her lover.
Her happiness, however, was shortlived when Silvia overheard a message from Pepa asking Sara not to say anything to Silvia about sleeping with Aitor. When Pepa returned, she confirmed Silvia's fears, and Silvia was once again broke off the relationship. She remained steadfast in her determination to ignore Pepa, though she missed Pepa terribly. When she could not do that, she asked instead to be friends. Pepa disagreed, and told Silvia she would only be with her as her girlfriend. When Pepa was involved in a near death experience with their colleague, and was traumatized from the event, Silvia found herself no longer able to ignore her feelings for her ex-girlfriend and went to the hospital to be with her. There, they reconciled. Silvia proposed soon after. Pepa said yes.