Taylor Sheats was nervous about her mother keeping guns in the family's Katy home

Credit: Source: Christy Byrd Sheats/Facebook

Taylor Sheats, the 22-year-old who was fatally shot by her mother last week along with her 17-year-old sister, worried about her mother owning guns, a childhood friend tells PEOPLE.

Taylor and Madison Sheats were fatally shot last Friday by their mother, Christy Sheets, who opened fire on them after calling a family meeting. Authorities say Sheats had a history of mental illness and that they had been called to the house three times for suicide attempts, though they did not specify whether the calls were in reference to Christy Sheats.

Matthew Wiley, a childhood friend of Taylor, says days before she died, Taylor expressed fear for her safety at home.

“She said, ‘There’s a gun in the house and it makes me feel uneasy,'” Wiley tells PEOPLE. “She felt so unsafe.”

Wiley and Taylor attended high school together at Seven Lakes High School in Katy, Texas, and lived two blocks from each other.

Wiley tells PEOPLE three days before she was killed, Taylor texted him and said she and her mom had gotten into a heated argument about her parents’ relationship, which Wiley says was shaky. Wiley says Taylor was scared about her mother having access to guns given her mental instability.

In recent years, says Wiley, Taylor and her mother’s relationship was tense. According to Wiley, Taylor told him Christy was growing anxious about her daughters’ growing up and moving out.

Taylor, who graduated from Lone Star College cum laude in 2015, was between jobs and preparing to marry her longtime boyfriend, Juan Sebastian Lugo. The two were set to be married Monday, according to a relative.

Taylor Told Him: ‘I Don’t Know What’s Going on with My Mom’

Christy’s “outbursts” affected Taylor, Wiley says. He says that while the 22-year-old was always smiling, she worried about her little sister getting caught in the middle of her family’s arguments.

“She always wanted to keep an eye on [Madison] and watch over her because she was scared for her of being in the middle of that situation,” Wiley remembers.

Taylor would call Wiley for advice on dealing with her mother and her mental illness. Wiley last saw Taylor in May when they got coffee and talked about family issues.

“She’d say ‘I don t know what’s going on with my mom. I feel like I should do something – maybe tell her to put the guns in a very safe place where she would forget where [they are]?'”

“I was like “Your mom wouldn t do that; you’re fine,'” Wiley remembers. “And then this happened. It makes me lose my breath just talking about it.”

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Different Views on Guns

Wiley says Taylor and her mom shared different views when it came to politics. On her Facebook page, Christy Sheats openly opposed gun control, but Taylor was pro gun control.

“[Taylor] was supportive of guns being in the right hands,” according to Wiley. “[Taylor] was very on edge about her mom having a gun with a mental illness.”

Wiley tells PEOPLE Christy Sheats was in the process of switching medications for mental illness. Taylor never told Wiley what her mother suffered from, but she told Wiley that Christy would stay up all night, get overwhelmed very easily and act out.

“She told me that her [mom’s] mood swings were [unpredictable],” Wiley says.