Many children of 9/11 victims were too young to remember their parents who died. They've grown up living with the tension between having a personal connection to the day but few, if any memories.

Transcript

LULU GARCIA-NAVARRO, HOST:

We are approaching the 20th anniversary of the 9/11 terrorist attacks. Nearly 3,000 people were killed on that day. Many of them left behind very young children who have grown up over the last two decades with few, if any, memories of the parents they lost. NPR's Melissa Block has some of their stories.

MELISSA BLOCK, BYLINE: The memories come, if they come at all, in fragments, a hazy glimpse, a faint echo.

MICHAEL TREROTOLA: There's not a lot that I know about my mom.

AMANDA TREROTOLA: I probably only have, like, two very cloudy memories of her.

AJ NIEDERMEYER: There's a picture of him with me in a stroller. And I'm holding this massive fish that's, like, bigger than I am.

ANGELICA NIEDERMEYER: I mean, I only know what I've been told. They used to call him Big Al.

AN NGUYEN: He would sing, sometimes very loudly. A lot of classical or traditional songs in Vietnamese.

BLOCK: We'll hear more from all of those voices in this story. That last voice is An Nguyen remembering his father, Khang Nguyen, who emigrated to the U.S. from Vietnam after the war. He was an electronics engineer who worked as a contractor for the Navy. Khang Nguyen was 41 when American Airlines Flight 77 crashed into the Pentagon, a direct hit in the area where he worked. An had just turned 4.

NGUYEN: And being so young and so vulnerable and also in the midst of the aftermath and all of that, it was a really difficult time.

BLOCK: There's a family photo of An, a small boy in khaki overalls standing outside the Pentagon just a few days after the attack. He's clutching an orange safety fence. Where the plane struck the building, a whole section is gone. As he's grown, an only child with few memories of his dad, An has had to reckon with huge life questions.

NGUYEN: In some regards, I'm on my own trying to understand how this world operates and, more - possibly more importantly, how do I know myself?

BLOCK: An is a software engineer soon to get his master's degree, a degree his dad was on track to get himself when his life was cut short. An sees his achievement as a gift for his father. He says, I know he would be very proud of where I've gone.

(SOUNDBITE OF CHIMES)

BLOCK: In a field in Shanksville, Pa., there's a memorial with a towering musical instrument, 40 wind chimes representing the 40 passengers and crew who died when United Flight 93 crashed there. LeRoy Homer was the co-pilot on that flight. He had fallen in love with planes as a little boy, would watch aircraft take off and land for hours. As a teen, he worked nights to save up money for flying lessons. And then...

LAUREL HOMER: He got his private pilot's license when he was 16.

BLOCK: ...That's LeRoy Homer's daughter, Laurel. She was still a baby, just 10 months old, when her father was killed in the crash. He was 36, a former Air Force pilot. For years, Laurel went to a camp for children who lost loved ones on 9/11 who all shared that same empty space at the heart of their family. She does wonder about the kids who had time to know and love their parents.

HOMER: It's definitely a hard place to be when you saw a future that you never got to have.

BLOCK: Laurel is a college senior now. She usually avoids memorial services on 9/11 and tries to ignore the constant reminders of what that day means.

(SOUNDBITE OF MEMORIAL, BELL)

UNIDENTIFIED PERSON #1: Kathleen Ann Nicosia.

UNIDENTIFIED PERSON #2: Martha Stewart Niederer (ph).

UNIDENTIFIED PERSON #1: Alfonse Joseph Niedermeyer.

BLOCK: Alfonse Niedermeyer, known as Big Al, was a Port Authority police officer who rushed to the World Trade Center to help with rescues. He was 40 when he died in the South Tower. Soon after his memorial service, his wife, Nancy, discovered she was pregnant with their second child, a daughter she named Angelica Joy.

ANGELICA NEIDERMEYER: I mean, Angelica Joy - I guess there was joy. And I guess because Angelica means messenger of God.

AJ NIEDERMEYER: I've told you this before, Angelica, but you were one of the best things that could've possibly happened right then and then every year after that. It was huge for mom and huge for me, too.

ANGELICA NEIDERMEYER: Thanks.

BLOCK: Angelica's older brother is named for his father and goes by AJ. He was 2 1/2 on 9/11, a little over 3 when Angelica was born.

ANGELICA NEIDERMEYER: I do remember when AJ would miss our dad, and I would try so hard to understand. You know, like he would say like, oh, I miss daddy. And I'd be like, well, I miss him too, you know, like, even though I didn't even understand what that meant.

AJ NIEDERMEYER: Yeah. I think for a long time, Angelica really - I mean, I don't want to speak for you, but I think it meant a lot to you - the fact that I had those 2 1/2 years. But, you know, I was so young, and there's so much that I don't remember.

BLOCK: Angelica and AJ say the larger-than-life hero narrative wrapped around the story of the 9/11 first responders can overwhelm their intimate personal loss. Later this month, AJ will head to grad school. Angelica is a college sophomore. On 9/11, their family tradition is to visit the memorial at Ground Zero and touch their father's name inscribed in bronze.

(SOUNDBITE OF VIDEO)

UNIDENTIFIED PERSON #3: Look at Lisa's belly. Two twins.

LISA TREROTOLA: Seventeen weeks. Starting on my fifth month.

BLOCK: A home video, New Jersey. We see Lisa Trerotola hugely and happily pregnant with the twins she'd had a hard time conceiving. Amanda and Michael would be 3 1/2 when their mom was killed in the north tower of the World Trade Center. She was 36, an administrative assistant for the Port Authority.

M TREROTOLA: And I feel like I sort of recall that someone asked if she was coming home. And I remember my dad replying that she isn't coming back.

BLOCK: But beyond that, the twins weren't told what happened. They had a vague idea their mom had died in a fire. They don't remember a funeral. Their dad soon remarried. Liz, whom they called their new mom, became the mother they knew. And it wasn't until they were 11 years old that their father and Liz sat them down and told them the truth - that, in fact, their mom was killed in the attacks of 9/11.

A TREROTOLA: And I just remember, like, my brother tucking his head in the pillow and just crying his eyes out.

M TREROTOLA: It was just utter shock.

BLOCK: The twins were finally told the reality when their parents thought they were old enough to understand it - terrorists, hijacking, towers collapsing.

A TREROTOLA: Honestly, it just felt like the world got a lot smaller at that moment, and it wasn't as safe anymore.

M TREROTOLA: I agree. That moment just still sticks out to me because it's so world-crushing. And what you thought you knew isn't what is.

BLOCK: Amanda and Michael have never gone to see the September 11 Memorial at Ground Zero. They try to keep their mother, Lisa, close in small ways. Amanda remembers when she took her driving test to get her license. She brought along a photo of her mom holding the toddler twins.

A TREROTOLA: And afterwards, I did find out I passed. And I remember, like, taking the picture out of my center console and just, like, saying, mom, I did it. You would be so happy. I really wish you were here to, like, see me. I just was overjoyed. And at one point I kissed the picture and I was like, see - I did it, mom.

(SOUNDBITE OF YOUNG OCEANS' "FACE OF THE DEEP")

BLOCK: Melissa Block, NPR News.

(SOUNDBITE OF YOUNG OCEANS' "FACE OF THE DEEP") Transcript provided by NPR, Copyright NPR.