From the article:
Katelynn Johnson, a senior sociology-psychology major, identified herself in a letter to the Collegiate Times as the person who added the stone for Cho.Link copied from kitten_goddess.
"My family did not raise me to do what is popular," she wrote in her letter to the campus newspaper. "They raised me to do what is morally right. We did not lose only 32 students and faculty members that day; we lost 33 lives."
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