Whatever did happen to the pretty 23-year-old woman, her parents, Richard and Linda Malonson, have not seen or heard from their daughter in seven years.
Malonson grew up in Littleton and attended Columbine High School.
She was a freshman on April 20, 1999. On that day the A-student and talented softball player was in the school's library when shots rang out and students began screaming.
"At first she thought someone was pulling a prank," her father Richard Malonson said.
But Dylan Klebold and Eric Harris were systematically going through the school, setting off bombs and shooting students. The two friends killed a dozen fellow students and a teacher before committing suicide.
"When she realized that it wasn't (a prank) she ran," Richard Malonson said. "She made it out of the building. She called her mother."
Linda Malonson picked her daughter and some friends up and took them to their home on 7400 block of South Zephyr Court.
Brandi Jo knew several of the victims including Isaiah Shoels, 18.
Her sister, Monica, was a senior at Columbine High School at the time.
"Both of my girls were very much affected by the events of that day," Brandi's mother, Linda Malonson, wrote in a Facebook page called Help Find Brandi Jo. "Many of their friends died that day. This day was the start to what changed our lives forever."
Richard and Linda wanted their daughter to get counseling but she refused.
"She was the kind of girl that took care of others first and not herself," her mother wrote. Still, "she seemed to be doing okay."
The following year on Valentine's Day, Brandi Jo lost two more close friends.
High-school sweethearts Nicholas Kunselman and Stephanie Hart-Grizzell were shot to death on Feb. 14, 2000, in a Subway sandwich shop a few blocks south of Columbine High School.
Brandi Jo was only a sophomore in high school at the time.
She was a junior at Columbine when a close friend of hers left Brandi a phone message. She was the last person he called before committing suicide on Nov. 10, 2000.
"All three of these horrible (tragedies) devastated her," Linda Malonson wrote.
The first hint of trouble for Brandi Jo came less than a month before the third anniversary of Columbine in 2002 when she was arrested for theft. She was charged with a misdemeanor.
Brandi Jo graduated from Columbine High School two months later.
She became a certified nurse's assistant and took care of elderly people.
"The last lady she took care of had multiple sclerosis and Brandi moved in with her to take care of her," Linda Malonson wrote.
Brandi Jo had two jobs and began taking nursing classes at Parks College.
"She was a very responsible girl, purchased her own car on her own and always paid her bills on time," Linda Malonson wrote.
But the family would learn that Brandi Jo had also started using illegal drugs. A friend introduced her to methamphetamine.
"Things started to change; we found out that a girl Brandi met at Parks introduced her to meth," Linda Malonson wrote.
The friend told Brandi Jo that methamphetamine would help her lose weight and make her feel better. Brandi Jo was still deeply affected by her friends who committed suicide or were murdered.
"I think she was overwhelmed with all that stuff," Richard Malonson said. "All that hurt had a big impact on her."
Brandi Jo started acting erratically. She would disappear for months at a time. There wasn't much her family could do about it because she was an adult.
When Brandi Jo finally did admit to her parents that she was using drugs, they arranged a therapeutic intervention and enrolled her in counseling.
"Never in a million years would you think that your daughter would get mixed up in drugs," Richard Malonson said.
But once again, because Brandi Jo was an adult, there was little her parents could do when she decided to leave home or started using drugs again.
Brandi Jo's drug problem led to financial troubles. In 2005, she declared personal bankruptcy.
She was convicted of drug possession and identity theft charges and sentenced to probation on Dec. 22, 2006.
"She told us she really wanted to get off of the drugs and take care of herself. She was just so sad, it hurt so bad to see her like this," her mother wrote.
Four days later, on Dec. 26, Brandi Jo told her father that she was going out.
"She was going to a friend's house," he said.
But Brandi Jo didn't come home that night or for several days. It wasn't the first time that she had disappeared so her parents and sister initially weren't alarmed much. They thought that their daughter might have being trying to skip out on her probation requirements.
Later a man called and said someone had killed her and put her in the Platte River, Linda Malonson said.
It was about a month after she had disappeared. The Malonsons filed a missing persons report. They gave investigators phone numbers of friends they found in her bedroom, Richard Malonson said.
During the investigation, some wildly different versions of what had become of Brandi Jo began to surface.
One explanation was that she overdosed on drugs and her body was dumped. Another friend said she was murdered and her body was dumped in a lake. Another person told authorities a killer hid her body in the mountains.
Sheriffs investigators looked into many leads, but "nothing has panned out."
Seven years have passed since Brandi Jo went missing.
"You pray for a miracle," Richard Malonson said.
Anyone with information that could help solve this case is asked to contact the Jefferson County Sheriff's Office at 303-277-0211.