Melanie Alexander

Sam is a nurse and single mother; she has a son, Alex (played first by Oliver Davis, later by Dominic Janes). Alex was born when she was fifteen; she has had to raise him mostly on her own. She comes from a family of losers and alcoholics; her anger towards Abby Lockhart in Season 14 when Abby tells the staff she had a relapse while working is explained when she tells Abby that she came from a long line of drunks who never tried to stop drinking.
Viewers first meet Sam in the Season 10 episode "Out of Africa," where she distinguishes herself by quickly and effectively giving an intravenous sedative to an unruly patient, even impressing the usually stubborn Dr. Romano. Sam shows herself to be an assertive, experienced, and talented nurse throughout the episode, though she loses her professionalism a bit when she discovers Dr. Luka Kovac`s unknowing part in her son Alex`s diabetic fit while he befriends the boy. She replaces Abby Lockhart who was head nurse, but decided to become a doctor instead. Her no nonsense attitude had gotten her in trouble early on. In the episode `Death and Taxes`, she hid Dr. Robert Romano`s mechanical hand after accusing the ER Chief of touching her inappropriately with the device .In addition, in the episode "Impulse Control", she punches an assault victim`s abusive boyfriend in the face when he threatens her as she tries to call the police, but overcomes Kerry Weaver`s knee-jerk lack of support and helps the abuse victim follow through on pressing charges.
Sam soon notices a bond between Alex and Luka. Though initially uncomfortable with Luka`s involvement with Alex, Sam eventually accepts it and becomes good friends with Luka. Later, a romantic relationship develops. Unexpectedly, Alex`s father, Steve, returns and attempts to push Luka out of their life. When she discovers Steve might stay permanently, Sam panics, packs up, and runs away. Before doing so, however, Luka runs to her, trying to get information from her as to why was she is doing this. Ignoring him and his slams on the car, fighting tears, she drives away. Sam has had a history of picking up and moving around the country to escape Steve. She worries that he will ruin her and Alex`s life and that they cannot coexist with Steve.
She does come back thanks to Luka who finds her at a motel and brings her back. They move in together. Throughout season 11, Sam and Luka lived together, and Luka was a surrogate father for Alex, even going and meeting with a school official after Alex got caught with an issue of MAXIM magazine. At the end of season 11, Alex runs away to find Steve, by hitchhiking after a confrontation with Sam. He is out to find Steve in Colorado, even though Sam has hidden the fact Steve is there because he`s in jail on robbery charges. Luka and Sam are frantically searching for him in the opener of season 12. Sam is desperately worried about Alex because of his diabetes, and his lack of insulin could have resulted in a coma or even death. Sam immediately gets in the car and drives non-stop to Colorado. Luka worries about Sam because they have been driving non-stop, and even hit a deer which completely destroys the windshield. Sam and Luka finally find an exhausted but stable Alex at a Canon City hospital, where he claims he`s okay and that he knows how to take care of himself. After a tense conversation about Sam and Luka`s relationship and their future together, they get to agree to disagree that Luka wants more kids and that Sam doesn`t, saying that "I`m done having kids." She breaks up with Luka soon afterward and moves into her own place with Alex. Alex`s father is then transferred to a jail in Illinois. In the Christmas episode, she lets Alex visit his father in jail after finding out he`s been telling a friend that Steve is dead.
Later in season 12, a very wealthy patient named Richard Elliot, played by Armand Assante, enters the ER. He suffers from a debilitating disease in where he needs an in-home nurse. He takes a liking to Sam and offers her the position of head nurse. He reassures her that she would still be able to keep her job in the ER while being his in-home nurse. Since the offer was being an in-home nurse, he invited her to live in a section of his mansion for convenience. She denied at first, but later on, she finds out that Alex cannot be in the tutoring program because of the lack of funds. She arrives at the man`s house, and asks if the offer still stands.
She has now moved into the mansion with Alex and is living a good life. Sam even took a chauffeured ride to work, causing her co-workers to speculate. Luka even inquires about how she is, probably curious to learn more.
In the 12th season finale, "21 Guns", Steve, a medical assistant named Mary and another prisoner named Rafe hatch an escape plot: Steve and Rafe injuring themselves and then escaping from the hospital. They stab Luka with a syringe as Sam looks on in horror. Because the syringe co