"Your backpack is ugly and so are you," her peers would say, laughing at her Justin Bieber bag.
The normally happy-go-lucky kid was hurting inside, badly.
The cruelty from her peers persisted for years.
But with help from teachers, social workers, therapists, friends and her parents, Katie was able to find a way out.
"If your’e in a situation like I was, go get help," the 11-year-old said.
"If your parents don’t want to talk or if they’re busy, find a teacher or adult and tell them what’s going on."
Kate is sharing parts of her story as Lisa Lane in the short film "Alone With The Darkness," by Frank Gigante -- world renowned for his fight against bullying (WATCH TRAILER ABOVE).
Kate's mom, Irina Cytowicz Tesoriero, plays her on-screen mom, Judy Lane, in the film.
"Alone With The Darkness" is about a girl who is being bullied but can't communicate what is going on to her family. A teacher she confides in becomes her support network and breaks down about the bullying that haunts her students every day.
"It really hit home for us," Cytowicz Tesoriero said.
"It shows that you get so wrapped up in life that basic signals and points are so easy to miss. Educators, neighbors and friends need to watch out for each other's kids."
"Alone With The Darkness" parallels many aspects of Katie's life. Her mom's job involves a lot of traveling. Her school's social worker, Elizabeth Schulman, had an open-door policy with Katie, who became close with Schulman's daughter.
Like her character, Lisa, Kate had trouble articulating what was happening at school to her parents.
"Her therapist gave her a notebook," Cytowicz Tesoriero said.
"Kate agreed that if there was something she wanted to talk to us about, she would write it in the book."
She left the notebook on a table or counter, where her parents would go through it regularly.
The habit slowly built the family's communication and they were able to learn how to deal with the situation.
Kate and her mom are hoping "Alone With The Darkness" will help others get the help they need.
The film will be released the first week of February. Check Frank Gigante's website for screening dates.
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