Ellie Porter was a prostitute known for being the birth mother of Noah Porter.
Background
Ellie bounced around from foster home to foster home while growing up, and was at some point seduced by Johnny Drake (alias Johnny D.) into the sex trade. Ellie was taken to his warehouse, where Johnny D. raped her repeatedly to break her. She eventually was sold at the age of sixteen to Little Tino, who also had sex with her, and developed a crack and heroin problem. Unbeknownst to Johnny D., Ellie became pregnant with his child and Little Tino let her keep it. One night, when she eventually overdosed around Christmas of 2013, Little Tino lied to her, saying her baby died suddenly. In reality, he sold him to a couple of child-rape videographers who had sold him a ten-year-old girl before.
On SVU
She first came into SVU's crosshairs when she started helping Little Tino rob tourists she was hooking up with and Tino eventually raped one of them, named Hans Erhard, with his gun. After that, Ellie seduced another john and signaled Tino. After they robbed him, SVU busted in. Ellie tried grabbing Tino's gun, but was stopped by Sergeant Benson and is arrested by her. Hans later identifies Ellie in a line-up but failed to pick out Tino. Benson and her lawyer Trevor Langan try to get her to cooperate against Tino. She refuses and is taken to central booking.
She is later brought back after it is revealed that Baby Boy Doe is her son and use that as leverage to make her cooperate. Eventually, the truth on Noah's disappearance is revealed, and she agrees to cooperate and get clean for Noah's sake. She gives them the house where Little Tino and his mother housed all the babies and fellow prostitutes. She is then transferred to Rikers, where Benson brings Noah for a visit. She is then taken to a halfway house, where Benson tells her to focus on testifying for the grand jury and get better for Noah's sake. Unfortunately, Ellie skips out during dinner to go out to get high. She is then cornered by her former employer's gang, gang-raped, tortured, and set on fire by a total of six people, all of whom got the green light by their boss to do it. (SVU: "Spring Awakening")
Four months after Ellie's death, everyone who had a hand in her death directly or indirectly are either arrested or deceased. (SVU: "Girls Disappeared")