Yolanda Guerra Koon was known as a pillar of her Siouxland community, a woman with a heart of gold and an unforgettable sense of humor. Born in Roma, Texas, and raised in Pharr, Texas, the 76-year-old female was a devoted member of the Catholic faith. She married Raul De La O in 1970 and together they had four children: Ana Maricela, Alicia, Hector, and Amanda. Yolanda worked tirelessly to provide for her family, and her children, grandchildren, and great-grandchildren were her greatest loves.
She was known for helping new residents transition to the Sioux City, Iowa, area, providing interpretation services at clinics and job sites. She also offered comfort and support to victims of domestic violence and sexual assault, always reaching out to family and friends to let them know she cared.
Tragedy struck on the morning of Saturday, September 26, 2026. At approximately 8:15 a.m., the Sioux City Police Department received an emergency call from inside a residence at 3110 Douglas Street, just a few blocks from Grandview Park. When officers arrived at the home, they discovered a horrific scene. Inside, they found three people deceased from fatal gunshot wounds. The victims were identified as Yolanda Guerra Koon, her 42-year-old daughter, Amanda McCauley, and Amanda’s husband, 42-year-old Andrew McCauley.
The subsequent investigation by the Sioux City Police Department determined the incident was a murder-suicide. Investigators concluded that Andrew McCauley shot and killed his wife, Amanda, and his mother-in-law, Yolanda. As police officers were arriving at the house, Andrew McCauley then died from a self-inflicted gunshot wound. The investigation into the shooting remained ongoing as of late September 2026, but authorities had identified Andrew McCauley as the sole perpetrator.
The violent deaths sent a shockwave through the quiet neighborhood and the broader Siouxland community. A neighbor who lived across the street, Jeff Peterson, told a local news station that such events were highly unusual for the area. He emphasized the importance of the community coming together in the face of such a tragedy. The loss was deeply felt by many, including a staff member at the Crittenton Center in Sioux City, who was mourning the loss of her aunt and cousin.
In the wake of the killings, the community rallied to support the two young children of Amanda and Andrew McCauley, ages 8 and 13, who were left orphaned. The Crittenton Center began collecting donations to help with funeral expenses and to provide for the children's future care. The organization stated, "These children’s lives have been forever changed and we want to show them that they will be taken care of by not only their family but the Siouxland community." Donations of cash, checks, and gift cards were accepted to go directly to the children's care.
Family and friends gathered to remember and honor Yolanda’s life. A visitation was held on Sunday, October 4, 2026, at Mohr & Becker - Hunt Funeral Home in South Sioux City, Nebraska, followed by a Rosary that evening. A Funeral Mass took place the next day, Monday, October 5, 2026, at St. Michael's Catholic Church in South Sioux City, with burial following at St. Michael's Cemetery. Yolanda was preceded in death by her daughter Amanda, her parents, a brother, a sister, and other beloved family members. She was survived by her three other children, numerous grandchildren, great-grandchildren, and her siblings. The case was closed by police in September 2026, with the primary suspect deceased.
