General Hospital lab technician Ellie Trout became part of the Port Charles scene when she met private investigator Damian Spinelli. He needed some lab tests covertly run to confirm that his friend and partner Sam Morgan had not lost her son at birth. Ellie sympathized with Damian and ran the necessary tests. Eventually, Sam was reunited with her living son and Spinelli acknowledged the important role Ellie had played in the reunion. Ellie and Damian quickly realized they had many things in common and started dating.

Ellie's relationship with Damian became serious and they became lovers. Ellie met Damian's good friend Maxie Jones and moved into her apartment, unaware that Damian and Maxie had once been engaged. When Ellie learned about Damian's past with Maxie, she questioned Damian's feelings for her and wondered if he was only with her because Maxie was unavailable. Damian assured Ellie that she was the one he wanted to be with and proved it by choosing Ellie when Maxie confessed that she wanted him back.

Ellie briefly broke-up with Damian while she dealt with the news of Damian's history with Maxie. Ellie felt as though Damian put Maxie's needs ahead of hers. Damian begged her for another chance and invited her to meet him on the rooftop of General Hospital on New Year's Eve. Ellie decided to reconcile with Damian but on her way she was hit by a car and rendered unconscious. When Ellie awoke in the hospital after surgery, she feared she was paralyzed. As Ellie dealt with the aftermath of the accident, Damian visited her and confessed that when Ellie had not shown up for their date, he had slept with Maxie. Damian insisted it was Ellie that he wanted to be with and he remained by her side while she regained the use of her legs. Ellie forgave Damian and they reconciled. Their relationship was tested again when Ellie worked on deciphering a relish recipe for A.J. and Michael Quartermaine while Damian was hired by Tracy Quartermaine to retrieve the recipe. Damian took the recipe from Ellie but destroyed it instead of handing it over to Tracy.

After Ellie and Damian worked through the relish subterfuge, they started to question their future compatibility. Damian shared that he longed to be a father one day while Ellie confessed that she did not plan to have children. When neither was able to change the mind of the other, Ellie and Damian decided to move forward with their relationship. Meanwhile, Maxie chose to be a surrogate mother for her best friend Lulu. As Maxie's pregnancy progressed, Ellie noticed Damian's interest in the pregnancy and wondered if he could be happy without children.

Although the issue of children remained unresolved, Damian and Ellie attended the Nurses Ball together. During the event, Ellie overheard a conversation between Maxie and her father in which Maxie admitted that she was keeping a secret about the baby. Ellie worried that something was wrong with the baby and hacked into Maxie's medical records when Maxie refused to share the secret. Ellie regretted her actions immediately when the records showed that Maxie had miscarried Lulu's child but had become pregnant again. However, the child she was carrying was the result of the New Year's Eve tryst with Damian.

Ellie was stunned when she realized that Maxie planned to give Damian's biological child to Lulu. Her first reaction was to tell Damian until Maxie convinced her that the truth about the baby would push Damian right into Maxie's arms. Ellie agreed to keep the secret but the truth weighed heavily on her conscience. On the night Maxie gave birth, Damian was present at the hospital and he was mesmerized by the sight of the newborn child. Against Maxie's wishes, Ellie informed Damian that he was the father of the baby Maxie had given birth to.

Damian was furious with Ellie over the deception and pushed her away as he processed the news. She understood his anger and reminded him that she still loved him before giving him the space he needed. When Damian decided to fight for custody of his baby, Ellie offered her support and Damian chose to forgive her. Shortly after Damian was awarded sole custody, Ellie was offered her dream job in Portland, Oregon. She planned to turn down the position until Damian suggested that he and his daughter make the move with her. Ellie accepted and they left Port Charles together.

Several months later, Carly Jacks and her boyfriend Franco paid a surprise visit to Ellie and Damian in Portland. Carly and Franco were in need of Damian's technical support and during the visit, Ellie and Damian shared that they had adjusted well to the life in the new city with Damian's daughter Georgie. When Maxie regained visitation rights with her daughter, she also made the trip to Portland. Ellie observed Damian's interactions with the mother of his child and Ellie believed that he was still in love with Maxie.

Ellie ended her relationship with Damian and encouraged him to visit Maxie in Port Charles. She hoped that Damian would figure out which woman was in his heart. However, Ellie regretted her decision and traveled to Port Charles. She was disappointed to learn that Maxie and Damian had reunited. Maxie's ex-boyfriend Nathan shared Ellie's pain and they attended the Nurses Ball together. Ellie and Nathan hoped that Maxie and Damian would be jealous and realize what they had lost. Their plan worked. Damian recognized that he belonged with Ellie while Maxie and Nathan got back together.