Suddenly, the young wife and mother who worked in Brazil and relocated to New Jersey for her husband's career was gone.
"I am speechless and feel like the world stopped for some moments," said Cecilia Marques, a former co-worker at a company that specialized in travel to Brazil. "I had the privilege to get to know and work with Fabiola for some years, and I can say she was a great, talented" woman with a "big and genuine heart."
PHOTOS: Train crash in Hoboken
The 34-year-old made that kind of impression on those who knew her.
When she dropped off her toddler daughter at day care on Thursday morning, she barely had a moment to chat - but she did anyway.
"We had a good talk for like a minute," said Karlos Magner, the owner of the day care who also serves as co-director.
De Kroon sprinted off to the Hoboken Terminal.
A short time later, a train traveling too fast crashed, killing de Kroon amid falling debris and injuring more than 100 other people.
ABC News spoke to the victim's mother, Suelli Bittar, who lives in Brazil, over the phone.
"All I have to tell you that is that we have a fatality," she said. "My daughter a beautiful girl inside and outside. If you have seen some pictures of them you will understand what I am telling you. She was very intelligent. She had a beautiful career here in Brazil. She was senior at SAP and her husband had to go to USA to work. And then she quit her job and went with him, with our granddaughter. And I really don't know what else to tell you. It's a really hard time for us. We will miss her a lot but sure she will be continued in our granddaughter and we have to go ahead. That's it."
Maria Sharp, also a co-director at the day care, said de Kroon was very involved, always wanting to know how her daughter was growing academically.
"You just saw a smile on her face every time she came to pick up her daughter," Sharp said, "and that's what I keep seeing."
De Kroon worked for the software company SAP in its legal department in Brazil until earlier this year, when she moved to New Jersey after her husband got a job with an international liquor company.
SAP spokesman Andy Kendzie said the company was "shaken by the news" of the train crash and de Kroon's death. He said the company expressed its deepest condolences to de Kroon's family and friends and to all of those affected by the "tragic event."
De Kroon, who earned her master's degree in 2011 from Florida International University's College of Business, previously lived in Florida but was a Brazil native, according to her Facebook account.
Dolf Wiemer, a former LG Electronics co-worker who lives in Brazil, said he knew the couple well and in April had visited them before they moved to the U.S. De Kroon was excited about the change and her husband's major career move, Wiemer said.
The de Kroons, he said, were an international couple finding adventure as they moved to another country in pursuit of a better life.
"Even if this means that you have to follow your partner and have to get used to other cultures and ways of living," he said. "It is tragic that she had to be in such a bad place at that time while pursuing their dreams of life."
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