When Vanessa Guillen was a little girl, she dreamed of joining the Army, her family said.
The Houston native graduated César E. Chavez High School in 2018 and shortly thereafter enlisted, becoming a private first class who worked to repair small arms and artillery while serving with the 3rd Cavalry Regiment.
At some point, her family says she confided in her two sisters, Lupe and Mayra, that she was having problems while posted at Fort Hood, the sprawling Army base outside of Killeen, Texas.
Her sisters said Guillen, 20, told them and fellow soldiers that she was being sexually harassed by a superior and was fearful of reporting the incident because of potential retaliation.
Family attorney Natalie Khawam said while Guillen was taking a shower, a superior came into the bathroom, sat down and watched her.
Fort Hood investigators said on their Facebook page that they "have no credible information or report that Guillen was sexually assaulted."
While at work on April 22, Guillen was contacted by a fellow soldier, Specialist Aaron David Robinson, via text message to deliver paperwork regarding a machine gun that needed to be serviced, according to court documents.
After Guillen's disappearance, her Army ID, bank card and two sets of keys were found by investigators inside a workshop where she worked.
Khawam later said she was told Guillen and Robinson had an argument in the armory where they worked after she discovered his alleged affair with the estranged wife of a former soldier.
Later, as local police and federal marshals closed in on Robinson, he died by suicide.
Human remains discovered near Fort Hood were subsequently identified as Guillen, Khawam said.
Here's how the story has unfolded:
Officials within Vanessa Guillen's unit become aware she's missing, according to court documents.
The U.S. Army Criminal Investigation Command received notification from Guillen's captain that she was last seen on the Fort Hood base.
A search of Guillen's cellphone records, according to court documents, showed that one of the last persons she was in contact with was Aaron David Robinson.
CID investigators interviewed the 20-year-old Robinson, who told them that the day Guillen went missing he went to the off-post residence he shared with his girlfriend, Cecily Aguilar, according to court documents.
Robinson told investigators that he only left the house once, to go back to the base to log in on a computer to enroll in training, court documents show.
Vanessa's older sister, 22-year-old Mayra, started an online fundraiser to cover the cost of a private investigator and an attorney.
"My sister DID NOT sign up to the ARMY to be held AGAINST her will. We need to find her and get justice," Mayra Guillen wrote.
Investigators with CID talked to two witnesses who allegedly saw Robinson on April 22 leaving his work area with a large box that appeared "very heavy in weight," and place that box in his car before driving away, according to court documents.
Robinson consented to a search of his cellphone records, which showed that on the day Guillen went missing that he made several calls to his girlfriend, Aguilar, throughout the day into the early morning hours of April 23, according to court documents.
"She was afraid to report it. She reported it to her friends. She reported it to her family. She even reported to other soldiers on base, but she didn't want to do a formal report because she was afraid of retaliation and being blackballed, and she, like most victims, just tried to deal with it herself," Lupe Guillen, 16, told ABC News on July 1.
Lupe Guillen said the hashtags #FindVanessaGuillen, #IamVanessaGuillen and #WeAreVanessaGuillen have become a sounding board for other military members who say they've been victims of sex-related crimes while on duty.
The CID and The League of United Latin American Citizens increased the reward for credible information leading to Vanessa Guillen's whereabouts to $50,000 -- $25,000 from each organization.
Aguilar is interviewed twice by investigators. After giving a false statement that Robinson was calling her phone repeatedly because she couldn't find it, she told investigators that on the night of April 22, they took a "long drive" to Belton, Texas, to "look at the stars," according to court document.
Robinson's cellphone records corroborated Aguilar's story and placed the pair along the Leon River, according to court documents.
Investigators began to search near the Leon River, more than 20 miles away from Fort Hood. Despite detecting an odor of decomposition, no remains were found, according to court documents.
Texas Rep. Sylvia Garcia and the Guillen family met with Fort Hood leadership, who told them they suspected foul play in Vanessa's disappearance.
CID investigators interviewed Aguilar again, and she allegedly admitted that Robinson told her that he'd bludgeoned Guillen to death with a hammer, according to court documents.
Aguilar then told officials that Robinson placed Guillen's body in a box, placed the box in his car and drove his car to a gas station where Aguilar worked. Robinson then drove Aguilar to the Leon River, where he opened the box to reveal Guillen's body, court records show.
Aguilar told authorities the two of them then dismembered Guillen's body using a "hatchet or machete type knife" and buried pieces of her body in three separate holes, according to court documents.
Investigators then found unidentified human remains about 20 miles away from the base, near the area investigators previously checked, according to court documents.
The discovery came on the same day Guillen's family members announced they were seeking a congressional investigation into her disappearance.
"It is truly disappointing how Fort Hood Army Base, a military base, has not given answers to Vanessa's family," Khawam, the family's attorney, wrote on Facebook.
Khawam announced at a press conference at the U.S. Capitol that a suspect tied to Guillen's disappearance died by suicide, and that a second suspect, a woman, had been arrested.
At the time, neither Robinson nor Aguilar were identified.
The Guillen family and Khawam said the deceased male suspect was a superior officer who allegedly walked in on Vanessa as she was showering, sat down and watched her. Vanessa didn't report the incident, her family said, because she feared reprisals.
Khawam announced at the press conference, attended by veterans including Rep. Tulsi Gabbard, that she's planning to propose legislation to protect U.S. military soldiers from sexual harassment and sexual assault.
Gabbard said she knows "personally the strength of the chain of command. I also know and understand that fear Vanessa must have felt."
"I have long advocated for real reforms ... for them to report these incidents outside the chain of command," Gabbard added.
Investigators with CID identified Robinson as the deceased suspect who had been accused of killing Vanessa Guillen on April 22.
Military officials said at a press conference that Robinson was not Guillen's superior and that during their investigation they didn't find evidence of sexual harassment to confirm her family's accusations.
"And I am really sorry that I was not able to provide them the information sufficient to reduce their suffering," Major Gen. Scott Efflandt, deputy commanding general of III Corps at Fort Hood, said at a news conference.
The U.S. Attorney's Office Western District of Texas later identified Aguilar as Robinson's alleged accomplice.
Aguilar, 22, was charged with one count of conspiracy to tamper with evidence for helping dispose of Vanessa Guillen's body, authorities said.
Aguilar is expected in federal court in Waco, Texas, for arraignment on July 6. An attorney was not listed for her among online court records.
If convicted, she faces up to 20 years in federal prison and a fine of up to $250,000.
Khawam announced that the human remains discovered 20 miles from Fort Hood on June 30 were positively identified as Guillen.
"The Army has confirmed that the bones, hair and other remains found are Vanessa Guillen," Khawam said in a statement. "We are at a loss for words."
The Army Criminal Investigation Division has yet to independently confirm the identification. ABC News has reached out to Army CID for comment.
The Army Criminal Investigation Command confirmed that the human remains found near a lake about 20 miles from the Fort Hood military base belonged to Guillen.
The secretary of the Army has ordered a broad independent review of the command climate and culture at Fort Hood, Texas, in the wake of the murder of Guillen. Meanwhile, an Army official said Army investigators have found information that Guillen was harassed, but that it was not sexual harassment, as Guillen's family has claimed, and that it did not involve alleged killer Robinson.
A federal magistrate judge denied Cecily Aguilar bail after prosecutors revealed she expressed her desires to flee the country.
During a bond hearing federal prosecutor Mark Frazier told the judge that Aguilar made phone calls from jail where she told the person on the line that she had access to $5,000 to leave the country.
ABC News' Abby Cruz contributed to this report.