The victims were identified Saturday as 39-year-old Destiny Ann Pickett and her husband, 50-year-old Clifford Pickett of Rosenberg, and 39-year-old Trevor Lane White of Katy.
Destiny Pickett and White worked together, according to a Lamar Consolidated Independent School District spokesperson. She was an instructional coordinator for George Ranch High School. White was the head football coach and athletic coordinator at George Ranch High.
The investigation is ongoing and circumstances surrounding the deaths are still unclear. Police said there are no other suspects in this case.
The White family released a statement Sunday, thanking everyone for "the love, support and prayers for our family at this difficult time."
"We are praying for all those impacted by the loss in this tragedy, especially all the children. We don't understand and no words can express our sadness. We are heartbroken," the statement read.
Counselors are set to be at the school Monday.