(CNN) What Sneha Mehta remembers most is not so much the noise, the debris and the fear. It is instead the kindness of strangers.

She and her husband, Sameep, had just flown in from Abu Dhabi to Brussels on Tuesday when bombs went off in the airport and the ceiling started falling on their heads.

The arrivals area is below ground level, and it was difficult to know what to do. Sameep thought maybe they should drop to the floor in case gunfire broke out. But they decided instead to try to make it out of there.

Sneha and Sameep Mehta were in the Brussels Airport Tuesday when terrorists struck.

"I absolutely didn't know which direction to run in," Sneha told CNN in a phone interview.

She thought for a moment that she might die there. But she didn't fear death, she said. She was with the man she loved.

Then the moment passed.

She knew 'for sure' she would survive

Fortunately, the Mehtas knew the layout of the airport. They made their way to the parking garage. They saw people cowering behind cars and sobbing, too frozen with fear even to run.

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Police and rescue crews were on the scene almost immediately, doing everything they possibly could to help people.

But she knew she would survive. "I knew for sure," Sneha said. "I knew for sure."

It was for the sake of the baby. She is 16 weeks pregnant.

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The Mehtas ran onto the highway. A cab stopped to pick them up. The driver not only took them to the hospital, he also talked to them the whole way -- just what they needed at a time like that.

And then, at Sint Augustinus hospital, there was a beautiful moment: The ultrasound exam showed that the baby -- the Mehtas don't know yet whether it is a boy or a girl -- appeared to be healthy and content, safe in the womb, sucking its thumb.

'May you always be brave and healthy'

When she and her husband got home to Antwerp, Sneha felt she had to write a letter to her baby. Maybe it will be unsealed when the child is 16. Maybe later. She hasn't decided yet.

An earlier ultrasound of the Mehta's unborn child.

But she needed an outlet. And she needed, she said, to write the letter while the feelings were fresh and raw -- to capture them before they faded.

"Hi Sweetheart," she wrote.

"I don't know if we already acknowledged this with you in person, but when you were 16 weeks old, mum and dad were in an explosion at Brussels Airport.

"And no matter where humanity is today, I just want to tell you that life is a wonderful thing, and the world is really full of remarkable people.

"You didn't just give mum and dad faith and reason to live, you gave the awareness and presence of mind like never before.

"I felt more alive than I ever have, and I knew I had to protect you, so I was calm, composed and fully aware that we will survive.

"When we reached Sint-Augustinus emergency, and we saw you oblivious and sucking at your thumb at the ultrasound, and doing your general acrobatics, all the mistrust, hate and angst for the terrorist attack vaporized.

"I do hope with all my heart that you are born into a better world, and if not, then you do absolute best to make it that.

"You are absolutely precious to us, and have already been a hero today. I guess the world has sent so much love and hope your way, you owe your life to reciprocating that goodness.

"May you always be brave and healthy. We love you beyond words.

"Mum and Dad"

'Regardless of race, color or background ...'

And now, when she thinks of that Tuesday, Sneha thinks not so much of the few people so disfigured by hate that they perpetrated the attack.

She thinks instead of the emergency people doing their work and more, she said, with all their hearts. She thinks of all the drivers who stopped along the highway to pick up people sobbing at the side of the road.

She thinks of the community in which she lives. "And people are still coming together, regardless of race, color or background," she said.

She thinks instead of all life has to offer.

"It's a very unfortunate event," she said."But it's still largely a beautiful world."