The mother of a teenage girl killed earlier this month in a massacre at Santa Fe High School in Texas tells PEOPLE she challenged President Donald Trump‘s views on gun violence during his Thursday meeting with survivors of the mass shooting and families of the victims.

Trump, 71, repeatedly called the gunman “wacky” while speaking at the gathering, at a Houston military base, according to Rhonda Hart.

“He kept calling him [the shooter] this wacky kid who was wearing a wacky trench coat,” says Hart, whose 14-year-old daughter, Kimberly Vaughan, was fatally shot along with nine others in the May 18 attack in Galveston County.

At that point, Hart recalls, “I raised my hand and said, ‘I have something to say here. Let’s just get to the mental health part.”

She then explained that her daughter had anxiety, Asperger’s syndrome and attention-deficit/hyperactivity disorder and “took medicine daily.”

“I said, ‘[The shooter] might have been depressed, but he wasn’t wacky.’ But if that kid needed help, he needed to have proper access to it,” Hart says, “meaning you shouldn’t repeal the Affordable Care Act [one of Trump’s cardinal promises] and get them the help they need and take away the stigma of mental illness.”

She says she told Trump, “Mental illness needs to be addressed.”

“I said all that and he didn’t say anything,” she says. “He was just like, ‘Uhhhh …’ ”

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