Caitlyn Martin was just 4 when the Twin Towers fell in 2001.
She only remembers the silence in her family's Delaware home as images of the crumbling buildings played again and again on the TV screen.
"I'm one of five kids, so our house was never silent," said Martin, 18, who graduated from basic training last month on the anniversary of the terrorist attack. "But I could tell by the way my parents' faces looked as they watched it on TV that I was supposed to be quiet. Something bad had happened."
In the years since, she's learned the details of the surprise attack on American soil.
"When you grow up after something like that, every year in school (9/11) is remembered in a ceremony. You learn about it in school. Teachers reference it," she said. "It makes you aware that things like that can happen here. It made me want to protect people and this country."
And it was on her mind Sept. 11 of this year as she marched across Parris Island's parade deck to graduate from basic training.
"It's an honor to be a Marine on this day," she said, moments after the ceremony concluded. "It's one of the biggest honors I can imagine."
Sitting in the stands was Martin's family, including her father, Chris Martin, who is also a Marine who went through Parris Island in 1999.
"Watching her graduate on this day gives us a positive reason to remember this day," he said.