He described the father as someone who seemed in complete "disbelief".
Trotter suspected the man chose to deplane immediately after receiving the news, and then proceeded to sit in the airport.
Trotter said he couldn't stop thinking about this chilling moment during the flight.
"All I could think about is how it could have been my daughters ... you wonder what's going on in this world," he said.
When Trotter landed and gave the account to BuzzFeed News, he broke down in tears and said he wish he could have gone back "to give him a hug."
"I'm not sure he would have wanted me to reach out to him at the time," he said. But now he wished he did.
"I don't know if there's anything I can say to that man...my heart breaks for him."