The mother of one of Anton Lazzaro's alleged sex trafficking victims told jurors Monday about how she first noticed the glaring signals that something was wrong with her youngest child in fall 2020.

Her "tenacious," outgoing 16-year-old had suddenly grown withdrawn. Her grades took a dive. And she began making large cash deposits in their shared bank account.

An eventual and excruciating talk revealed the source: her high school junior was being paid for sex with an adult man.

"I was horrified," she said. "I couldn't believe that someone would do that to my daughter and lure her in that way."

That mother's tip to the FBI sparked a federal investigation that, alongside an existing state probe prompted by the parents of another alleged victim, led to the charges naming five alleged teen girl victims on which Lazzaro is now standing trial.

The mother's testimony — as well as that from three more alleged victims — started the second week of Lazzaro's federal child sex-trafficking trial in Minneapolis.

Monday ended with FBI Special Agent Richard Waller, the lead agent who investigated Lazzaro, on the stand. Assistant U.S. Attorney Melinda Williams told Chief U.S. District Judge Patrick Schiltz that Waller would be the government's final witness and that the prosecution would rest its case "well before noon" Tuesday.

Schiltz told jurors at the end of the day that "we are well on track to get you the case this week."

Waller, who will resume testimony Tuesday, walked jurors through his investigation of Lazzaro's dating profile on the Seeking Arrangement site geared toward "sugar daddy" relationships.

He said Lazzaro listed his net worth at $5 million and billed himself as a CEO of a "gold/oil company." Records linked him to usernames including PickyButGenrous and TheYoungSD, which Waller suggested signified "sugar daddy." His profile included numerous statements preferring "young attractive women" and the prosecution on Monday emphasized that Lazzaro wrote, "I love to meet girls under 18-25."

Lazzaro's co-defendant, Gisela Castro Medina, has testified that she and a friend who later became Victim A met Lazzaro through Seeking Arrangement in May 2020. Castro Medina, now 20, has since pleaded guilty to conspiracy and obstruction charges and said she helped recruit other teen girls for Lazzaro to pay for sex.

Victim E testified Monday that Castro Medina introduced her to Lazzaro on social media and that the then-16-year-old agreed to meet him at the Mall of America. There, she said, he bought her a $1,400 Prada purse as two friends shadowed them to make sure she was safe. He invited her to come back with him to his Hotel Ivy condominium in Minneapolis. She said she declined that day but later visited there alongside another girl, Victim D, and engaged in sex acts for money and vape pens.

"I just remember him calling us good girls," she said.

Victim D, whose mother preceded her on the witness stand Monday, said she was jealous of her friend's purse and wanted in on the benefits. She said that, aside from cash and vape pens, she also received a new iPhone after a sexual encounter with Lazzaro.

As her mother looked on in the courtroom, Victim D broke down crying as she described how she stopped eating, started drinking and began to isolate herself in the aftermath of meeting Lazzaro.

"I started to take three showers a day because I never felt clean anymore," she said. "My life changed. I was a completely different person. My innocence was stolen from me."

At various points during cross-examination of the two former friends, Lazzaro's attorneys zeroed in on the girls' willingness to visit Lazzaro and suggested a lack of pressure imposed on his part.

"He was friendly and immediately made you feel comfortable, correct?" attorney Daniel Gerdts asked Victim D.

Some of Monday's most heated testimony came during earlier cross-examination of Victim A, the first alleged victim in this case. Thomas Beito, Lazzaro's other defense attorney, dug into her history of drug abuse while at multiple points sought to illustrate that Victim A could not be controlled by anyone.

Beito took issue with Victim A's account of why Castro Medina later kicked Victim A out of her home, suggesting it was over Victim A's drug abuse. Williams later showed jurors statements to investigators from Victim A that she was kicked out because she eventually refused to see Lazzaro.

During their encounters together, Victim A said Lazzaro frequently commented on her young age and body. He grew angry when she tried to close her eyes or look away from the large mirror hanging above the bed, she said, and lamented how he couldn't legally record pornography with her because of her age.

"He would always tell me that I was his favorite because I have such a childlike body," she testified, noting that she was 16 and barely weighed 90 pounds when she was paid for sex multiple times with Lazzaro in 2020.

Through her testimony, Victim A walked jurors through the dissolution of her friendship with Castro Medina as their relationship became more transactional. As Victim A started seeing Lazzaro alone for sex, he sent her home with two envelopes of money — most of which went to Castro Medina.

Victim A later threatened to report Lazzaro to police if he did not give her the money that had been going to Castro Medina instead, demanding $900. Prosecutors have said Lazzaro later sent the girl and her parents a nondisclosure agreement that they refused to sign. Instead, they reported Lazzaro and Castro Medina to West Hennepin police at the same time Victim A was being questioned about vandalizing a car owned by Castro Medina's boyfriend.

Beito zeroed in on the timing of Victim A's first allegations of sex trafficking, and alleged that she tried to blackmail him into giving her money to not talk to police. Williams later showed jurors a Snapchat exchange between Victim A and Lazzaro in which Lazzaro, not the girl, proposed him turning over $2,000 for Victim A's silence and for her to "leave Gisela alone as well."

Victim A and her parents are now also suing Lazzaro.

During sex, Victim A testified Monday, Lazzaro would tell her that "Daddy was going to take care of everything."

"The money is going to take care of everything," she recounted on Monday. "I'm not going to have to worry about being homeless."

"Who's Daddy?" Williams asked.

"That's what Tony called himself," Victim A replied. "Nobody else called him that though."