18-Year-Old Was Just a Frozen Embryo When He Was Rescued from Katrina. He Has a ‘Twin’ Who Is 21

Noah Markham was in New Orleans when Hurricane Katrina hit — but he wasn’t actually born until two years later.

“I was there, but I wasn’t there at the same time,” 18-year-old Noah tells PEOPLE in an exclusive interview for this week’s issue. “All the [storms] after that I was there for, though.”

It sounds strange — because it is.

Noah’s early life is a remarkable story of how an embryo survived a hurricane and eventually became a person.

Now a young man, he has started a new chapter as an Army private first class and plans to follow in his father’s and grandfather’s military footsteps.

His parents, Glen and Rebekah, used in vitro fertilization to have their first son, Witt, on Aug. 19, 2004, about a year before Katrina hit. They had five more embryos stored at a fertility clinic in New Orleans.

Before the hurricane struck, 1,200 canisters holding frozen embryos, including the Markhams’, were topped off with liquid nitrogen and moved to Lakeland Hospital as part of the clinic’s disaster plan.

Glen Markham tells PEOPLE that then-Louisiana Gov. Kathleen Blanco approved a rescue team to go to Lakeland to save the embryos.

The best-case scenario was that the embryos could stay safely frozen for weeks. But with the power out and temperatures soaring above 100 degrees, the embryos might not survive.

A rescue was launched on Sept. 11, 2005, and the embryos were found intact.

“And Noah was one of ‘em,” Glen says. “They went in flat-bottom boats from different police agencies and got ‘em before they defrosted.”

Noah says that when he was younger, he thought he had just “pretty lucky.”

“The older I get, I definitely think I wouldn’t be here if not for them,” he says. “And I’m very, very thankful to people that saved me.”

Two years later, the Markhams decided to have another child. Noah, named after the Biblical figure and his famous Ark, was born on Jan. 16, 2007.

He remembers his mom telling him that when he came home from the hospital, their family was surrounded by news people and photographers.

“They were just trying to get an interview with her because it really was a miracle,” he says. “It was all good news from something that was a lot of bad news.”

Glen, a retired New Orleans motorcycle police officer who now works for another agency, and Rebekah, a hospital administrator, later divorced but stayed in the same area as the boys grew up.

Noah says that as a child, “I was kind of popular and all the teachers, they played my video in class because you can go on YouTube and there’s videos about it.”

“So everyone really kind of already knew,” he says. “It just kind of sounds not believable. Nobody believes you were frozen.”

He adds that everyone who went through Katrina has a story worth remembering.

“There’s a bunch of bad, sad stories, but at the end of the day, you just feel closer to home because you are all connected by it,” Noah says. “My grandparents lost everything, including a self-playing piano that my dad always talked about and misses.”

Even 20 years later, parts of New Orleans still haven’t fully recovered. Noah hopes lessons were learned that will prevent similar destruction in the future.

For now, he is focused on the future. He graduated from Covington High School in the spring and entered Army basic training on May 28 at Fort Jackson in South Carolina. Now he is in advanced training at Fort Lee, outside Richmond, Va., studying to be a mechanic.

Noah and Witt will both serve at the same base — Louisiana’s Fort Polk — when Noah graduates in December.

There’s one more unusual twist to his origin story: He considers Witt his “twin” because they came from the same set of embryos, even though they are three years apart in age.

“That’s the hardest thing to explain to people,” Noah says. “I’ve been on this earth for more than 21 years — but technically, I’ve only been born for 18.”

He is excited to serve in his home state and plans to live there for the rest of his life, despite his unusual start.

“Property and items are replaceable,” he says. “At the end of the day, as long as you stay alive, that’s all that matters.”