(CNN) Democratic presidential candidate and businessman Andrew Yang became visibly emotional when discussing gun violence prevention with a woman who said she lost her daughter to a stray bullet.

During the Everytown Gun Safety Town Hall in Des Moines, Iowa, on Saturday, Yang was asked a question by a woman named Stephanie about preventing unintentional shootings by children.

Stephanie, who is from Las Vegas, said she lost her 4-year-old daughter Dayla when she was struck and killed by a stray bullet in March 2011. Her son, Dayla's twin, witnessed it.

"Firearms are the second leading cause of death for children and teenagers in the US, but 4.6 million American children live in homes with at least one gun that is loaded and unlocked, and hundreds of them gain access to a gun and unintentionally shoot themselves or someone else every year," she said to Yang. "As President, how would you address unintentional shootings by children?"

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