Holly was a homeless runaway. Her father died in a freak tractor accident, and her mother died of a drug overdose of Heroin when Holly was ten. She and her mother used to live in an orange van and were frequently on the road because they were getting kicked out of apartments after her mother couldn't keep up the rent payments.
After her mother's death, she was put in foster care (for the 5th time) and had been mistreated by a few couples, including the Fisks and the Benders. Holly had run away from the Fisks, but ended up getting caught in a short time. Then Holly was moved in with the Benders, where she would get locked in the laundry room sometimes with no dinner. Mr. Howie Bender was a creepy perv who was always touching her and he even popped the lock on the bathroom. Holly called him a pervert and she was sani-flushed and had no dinner. Mrs. Bender was a witchy wife who loved the shopping channel and stole fifty dollars from her husbands wallet to go shopping with. Holly was accused of stealing the money, and would be accused of other things like doing drugs and would be strip-searched. With the sani-flush incident, Mr. Bender told Holly that social services wouldn't believe her if she reported the incident to them, and Holly mentioned that the social worker didn't believe her about Mr. Fisk, when there was more evidence than a sani-flushed head.
In sixth grade, Holly had been bullied by a girl named Camille who was mean to her because of her background of being homeless. One day at recess, she was crying because Camille called her "a homeless freak with a face only my mother could love".When Holly had had enough of the system she ran away and managed to be on the run for five or sixth months. A more detailed look at Holly's background is in the novel, Runaway, written in journal entries.
When Sammy saw Holly, she thought she had an uncanny resemblence to her. They both wore high-tops and had blue backpacks. Holly had been described as a skinny girl in jeans and a sweatshirt. At the moment Sammy saw Holly for the first time, they both had their hair in pony-tails. Because of this, Dot and Marissa almost mistook Holly for Sammy. Holly also got a skateboard and is like Sammy when she rides it. On the cover of Runaway, there's a picture of Holly, and she is portrayed with brown hair and blue eyes.
Because of Holly's life on the run, she thought the world was cold. She used to not trust people who supposedly wanted to help her, and she knew that councelers didn't really understand what she was going through. She even almost attacked Sammy at first.
Hudson described Holly as "not afraid to jump into the fray". Holly can be just as tough as Sammy, sometimes even tougher, and she's had to scrape through life even more than Sammy has. Holly learned to survive in a cruel and hard world; learning to catch a ride on a moving train, shoplift (for necessities that she needed in order to survive, like food and water), ditch unwanted people who were following her, stowaway on a greyhound bus, etc.
Holly loves dogs and since her guardians work at a dog-grooming salon, she has a bond with them. According to Sammy, unlike herself, Holly seems to keep her bedroom neat and tidy and likes to be punctual and on-time. This could be because she used to have a tough life as a runaway and now values the things she has.
In Runaway, the story of Holly's six-month life on the run, she said that she disliked poems, but in the later journal-entries, she begins to write down poems and even dreamt about them in her sleep. Every since her mom died, Holly has missed her mom, and she doesn't know where she's buried even now that she's friends with Sammy. Furthermore, when Holly debuted, she initially had a habit or rummaging through the garbage, but it seems like she has shaken the habit in later books.
- Barehanded fighter- Holly knows a little about fighting; she and Sammy would watch the guys over at Slammin' Dave's Pro Wrestling School, and they would practice some of the wrestling moves they saw. In Sammy Keyes and the Psycho Kitty Queen, Heather and her friends followed Sammy and Holly, but when Sammy and Holly ditched them, Heather's friends could be heard saying that Holly was with Sammy, and that Holly was tough. In Sammy Keyes and the Wedding Crasher, Heather knocked Sammy off her skateboard and attempted to kick her, but before Heather could, Holly pushed her away and was able to punch her in the stomach, with Heather falling to the ground.
- Master plan maker- From Holly's life on the run, she's had to have had street-smarts and been able to come up with plans to get where she needed to go; she was able to make a plan to climb into a tree and jump down into a train, which ended up working. In order to stow away on a Greyhound bus, Holly created a distraction with a fire in a trash can. She also knows how to shoplift: stay close to an adult; look out for shoplifting mirrors; buy at least something so there won't be any suspiscion.
- Resourceful weapon maker- After buying a few materials, Holly was able to make a spear: a broom with a knife ducttaped to the pole.
- Vera and Meg Talbrook- Legal Guardians (Vera and Meg and mother and daughter)
- Unknown mother
- Unknown father
- Since Holly ran away from the Benders, she had been in five different foster homes.
- Holly is the only character in the Sammy Keyes Series to have her own solo novel, Runaway. This book is both a prequel and a tie-in, as events from the book take run alongside the Samantha Keyes novel The Sisters of Mercy.
- Holly's novel, Runaway, is one of only two books in the Sammy Keyes series not to be told from Samantha's first person view. The other was Sammy Keyes and the Kiss Goodbye, which was told in a third person point of view.
- From her background and experience in foster homes, she can smell a person and tell what type of drug they were using.
- When Holly and her mom were on the road, they would have KFC for Thanksgiving dinner.
- Holly's sixth grade homeroom teacher's name was Miss Leone, who gave Holly the journal that she wrote in and ultimately served as a major influence in her life.
- Holly could be from the Midwest; she wanted to go out west to California where it was warm, and she didn't want to be homeless in the snow when the Midwest is known for snow in winter.
- Even though Holly was mistreated in most of her foster homes, her first foster parents were kind and loving, but probably because her mother died, she didn't give love back; she regretted not showing love, and then she was adopted by Meg and Vera who she could give love and be loved.
- When Holly enrolled at William Rose Junior High, she, Meg and Vera made up a plan to tell the school that Holly transferred from New Mexico.
- Over the summer, Holly, Meg and Vera went on a road trip to places like Mount Rushmore, the Grand Canyon, etc. and they took a lot of pictures of Holly.
- Some time when Holly was in foster care, she had a horrible thing happen to her, and she wrote a poem about it, calling it her most embarrassing moment:
Naked in the Rain.
- Holly has been described as having a Melancholic temperament.