About 140 infants and toddlers were playing in the Defense Department's Child Development Center, approximately 30 yards from the Pentagon on September 11, 2001, when American Airlines Flight 77 crashed into the Pentagon.
Two sisters who were in the day care center that day were inspired by the heroism around them, and today, they're both in the U.S. military, committed to serving their country.
Second Lieutenant Hanna Born, just three years old at the time of the attacks, graduated from the Air Force Academy in 2019; her younger sister Heather is a midshipman in the Naval Academy's class of 2023.
Heather has no memory of 9/11 since she was just four months old, but Hanna still has some fragmented memories.
"I was in the day care center playing and dancing with some of my classmates," Hanna told CBS News in an interview in Washington, D.C. "We were playing with those dance ribbons, and then the next thing I can remember was kind of being in the hallway."
No children at the day care center died or suffered injuries from the attack on the Pentagon. Still, the Child Development Center closed in 2004 over fears about the children's safety. It was housed in a building on the Pentagon campus, across from where the plane crashed. Fear and panic enveloped the Pentagon and its auxiliary buildings after the plane hit and engulfed the west side of the Pentagon in flames.
"I began to feel sensory overload, especially after exiting the building. Because that's when you really saw just a groundswell of people coming out of the building," Hanna remembered. "Obviously, you had the noises from the fire alarms, you had basically every type of emergency vehicle, the sirens from that, and you had jets and helicopters from overhead making noise, and on top of that, just a really acrid smell from the burning jet fuel and smoke."
Hanna said service members soon arrived to evacuate the day care, since some of the workers were elderly and needed help moving the infants and toddlers from the building. They loaded the infants into cribs and carried the cribs to a park next to the Potomac River.
"I don't think we know really any of the names of anyone involved," Hanna said. "Despite not getting any public recognition for what they did that day, I just hope they know how their actions have inspired my sister and I and how we hope to pay it forward."
Hanna is now in graduate school at Georgetown University studying data science and analytics and hopes to fly search-and-rescue missions.
The sisters' parents, who also both have military backgrounds, weren't in the Pentagon on 9/11. Their mother, retired Brigadier General Dana Born, was at Joint Base Anacostia-Bolling at the time, while their father, a retired marine, had previously been stationed at the Pentagon.
In the days following the attack, their father took them to a hill overlooking the Pentagon so they could watch the recovery efforts as he tried to explain what had happened.
Brigadier General Born says that Hanna, as a child, would spend hours drawing pictures of her experience that day as she tried to understand what happened.
"We sat by her side the entire time to support and comfort her while also answering questions as she attempted to 'process' exactly what happened," said Born. "The more she drew, the less anxious she appeared, since she was gradually piecing things together from that horrific day that was difficult for even adults to comprehend."
Those events, combined with their upbringing on military bases, inspired the sisters to follow their parents into the military.
Over the last 13 years, the trees have matured and filled out, and now they provide shade and serenity.
Hanna says she and her sister visited recently and were struck by the poignant scene.
"When we had moved away from D.C., the trees were pretty small that they planted, and since then they've grown, so it's just kind of striking to see how much life is rising in that area."