The teen took the witness stand Wednesday in federal court in Alexandria. Shaking at times, she described being prostituted around the Washington area by two brothers she met at a Virginia motel.

Identified only as Danielle H. to protect her identity, the now-16-year-old testified that one of the brothers, Christian Hood, posted ads for her on the website Backpage earlier this year. His half brother Abdul Bangura was her boyfriend and her pimp, she said.

Hood’s trial on sex trafficking charges comes as Backpage is under increasing scrutiny for hosting prostitution ads that include child-trafficking victims.

Bangura, 21, pleaded guilty to four felonies just as his trial was about to begin this week, including the production of child pornography for a video he made of himself having sex with Danielle. He faces a minimum of 15 years in prison.

Hood has argued that there is no direct evidence of his involvement in Danielle’s prostitution; she testified that he met her in person only two or three times.

Abdul Bangura, left, and Christian Hood, right, seen in a Facebook photo, are accused of prostituting a 15-year-old girl in the D.C. area. (N/A/U.S. Attorney's Office for the Eastern District of Virginia)

The first time, Danielle testified, was in February when she was living in an Econolodge Inn in Dumfries, Va., with her aunt.

She told him that she was 17; she later told his brother that she was 16.

“I thought, that’s the way for them to talk to me,’ ” she testified.

According to court documents, Hood promised her “money and progress” and asked her to send him photos he could post on Backpage.

In her Backpage ads, the 4-foot-8-inch Danielle was advertised as “fun size” and “unforgettable.”

“This is a case about how an adult man exploited a vulnerable 15-year-old girl,” Assistant U.S. Attorney Kyle P. Reynolds said in his opening statement. Danielle, he said, was “naive” and “immature.”

Bangura admitted that he would act as “security” for Danielle, driving her to motels, checking in on her during paid dates, providing her with condoms and taking a portion of the money she earned. At night, they slept together.

“I’m really starting to catch some feelings,” she said in one text conversation. “I may not seem like the girl for you, but I am.”

She asked him to delete an “ugly” video he recorded of her having sex with him, but he refused, according to text messages presented in court.

Asked whether Bangura returned her feelings, Danielle testified that now, “I’m not sure.”

She is pregnant with his child, according to court documents.

Prosecutors said that Hood was involved in prostituting four other people on Backpage. He allegedly sent a text message in March asking someone named “Peach” for help finding more women: “ask the homies out there if they know any freaks that’s trynna work on bp I’ll show you how to make the ads n all that.”

Defense attorney Douglas Steinberg emphasized that Danielle was engaged in prostitution before meeting Hood and that they interacted in person only two or three times.

Danielle said she had previously been prostituted on Backpage when she was 14, by another pimp named T.J. According to the testimony of FBI agent Alix Skelton, Danielle’s mother also was involved.

She was located after a tip came in to the National Center for Missing & Exploited Children that she might be a child-trafficking victim.

Anti-human-trafficking advocates have been pressuring Backpage for years to stop hosting prostitution ads. Documents published by The Washington Post last month show that the website does not just host but solicits sex-related ads. Members of Congress have pushed for a criminal investigation into the site.

But some trafficking opponents argue that the website’s willingness to work with law enforcement makes it a useful tool for finding victims.