"Although she was an accomplished teenager with a bright future ahead of her, unfortunately in one impetuous moment, she made the rash decision to end her earthly life," the family said in the statement.
"She won countless crowns & trophies after competing on the pageant circuit her entire life ... Her highly acclaimed talent as a contortionist had already led to professional touring job offers, and she had recently been selected to be a cheerleader at her high school next fall," the family added.
On Tuesday, TMZ reported the death of the 16-year-old, best known for her time on the TLC show chronicling families preparing their children to compete in beauty pageants.
"I don't have words or any thoughts. A beautiful baby girl is gone," Kalia's mother posted at the time of her death via TMZ. "Please give us privacy as we mourn the loss of Kailia. My baby forever"
A clip of Posey from the television show has since become the popular "grinning girl" gif online.
Posey's family has set up a fund at the Whatcom Community Foundation in her name in an effort to "help get much needed resources to students in crisis."
If you or someone you know is at risk of suicide please call the U.S. National Suicide Prevention Lifeline at 800-273-8255, text HOME to 741741 or go to SpeakingOfSuicide.com/resources for additional resources.