On December 20, 1984, twelve-year-old Jonelle was dropped off by friends at her family's residence located in the 300 block of 43rd Avenue court in Greeley, Colorado where she had returned from a Christmas choral program at a nursing home where she had sung with her middle school choir. She was supposed to wait for the rest of the family to arrive home.
Jonelle's 16-year-old sister and her father, Jim were at a basketball game and her mother, Gloria was out of state visiting relatives. Jonelle was last heard from at 8:30 p.m. when she took a phone message from an acquaintance of her father.
When Jim came home at approximately 9:30 p.m., he discovered his daughter missing. Jonelle's stockings, shoes, shawl and a portable heater were on the floor and the television & lights were turned on. It is believed that Jonelle was interrupted while watching TV.
The garage door was discovered open and investigators found footprints inside the garage and around the back of the family's home, but there were no indications of a scuffle in the snow of the yard. Authorities suspect that an unknown intruder or intruders broke into the house and abducted Jonelle that evening. She has never been seen again.
In 1997, Jonelle's biological mother, Terri Vierra-Martinez, located Jonelle's adoptive parents where she learned about Jonelle's disappearance at that time. She also discovered that law enforcement had kept Terri under surveillance for six weeks after Jonelle went missing.
Authorities were not permitted to give Terri any information concerning her daughter's case at the time due to adoption privacy laws. Terri is not considered a suspect in Jonelle's disappearance and she has become friends with Jonelle's adoptive parents.
Jim and Gloria believe that Jonelle is deceased and have held a memorial service for her. They now live in the Philippines.
Police have stated they believe local people know more about Jonelle's disappearance than they have stated; they theorize that Jonelle was abducted by somebody who knew her and lived in the community, and that possibly the perpetrator still lives in the area.
At the time of her disappearance, Jonelle attended Franklin Middle School and attended Sunny View Church of the Nazarene. As of 2020, her case remains unsolved.
Jonelle is described as a Caucasian female with brown hair, brown eyes, is 5'3 and weighs 115 pounds. She has a scar on her chin, has pierced ears and wore a full set of braces on her teeth at the time of her disappearance.
She was last seen wearing a light blue ski jacket, a red blouse, a dark gray sweater vest, a charcoal gray skirt and house slippers.