“I immediately thought, ‘It’s a mistake,’ or maybe she’s been robbed or something,” Knowles tells PEOPLE. “I kept telling myself, ‘This is not the same person.'”
Knowles adds, “She loves her daughters. I have no idea what could possibly make a mother who loves her daughters as much as she did – what could cause a person to snap?”
Police say the sisters, Taylor, 22, and Madison Sheats, 17, were killed by their mother, who allegedly started shooting at after convening a family meeting in the living room of their Katy, Texas, home before continuing to fire as they fled. Police say Christy Sheats went back into the home and reloaded her gun before coming out to shoot Taylor again. After a brief standoff with police when she refused to drop her gun, Christy Sheats herself was fatally shot.
“This is such a tragedy,” Knowles says. “The part of Christy that I knew was a very kind, loving mother. Within 20 seconds of meeting her, we were talking about her being a mom. That was her mission in life, that was her everything – her two daughters.”
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Knowles, of Huntsville, Alabama, and Sheats became instant friends last summer when Sheats traveled to her native Alabama to check on real estate she was considering for purchase. The land was owned by Knowles’s husband, in a small, forgotten railroad ghost town where Knowles had grown up called Taylorsville.
“Oh, that’s my daughter!” Sheats said upon hearing the name of her oldest daughter, Taylor.
Although the purchase didn’t go forward, the two women stayed connected and bonded through Facebook, texts and phone calls. At the time, Knowles had just published a historical novel about the area; Sheats voluntarily stepped up to help her new friend promote it. “She took me under her wing,” says Knowles.
“If you just met her, you would feel the same way I do,” she says. “She’s sweeter on the inside than she looks on the outside. Just a beautiful, beautiful person.”
“I can’t understand for the life of me, what could make any mother – but especially this one – how could they harm their children?”
She says she knew nothing about Sheats’s reported history of mental illness. Fort Bend County Sheriff’s Office had been to Sheats’s home “for previous altercations” involving her “mental crisis,” a sheriff’s spokeswoman previously told PEOPLE, declining to elaborate on those incidents.
“Never in a million years would have guessed it,” Knowles says.
“You just don’t know what makes people flip that switch,” she says. “I’m still just in shock. I’m in disbelief.”