Subscribe | UPI Odd Newsletter Subscribe Dec. 9 (UPI) -- A mother and her young daughter, who was traveling with an oxygen machine, had the opportunity to fly first class after a man gave up his seat. Kelsey Zwick shared a photo on Facebook as she and her 11-month-old daughter sat on the American Airlines flight from Orlando to the Children's Hospital of Philadelphia after a flight attendant informed her the man offered to switch seats. Advertisement "To the man in 2D. Today you were traveling from Orlando to Philly. I don't know you, but I imagine you saw us somewhere. I was pushing a stroller, had a diaper bag on my arm and also lugging an oxygen machine for my daughter," Zwick wrote. "We pre- boarded the plane, got cozy in our window seat and made jokes to those around us about having to sit by my yelling-but-happy baby." After settling in for the flight, Zwick said she was overcome with emotion upon learning she and her daughter would have the opportunity to sit in first class. "Not able to hold back tears, I cried my way up the aisle while my daughter Lucy laughed! She felt it in her bones too ... real, pure, goodness. I smiled and thanked you as we switched but didn't get to thank you properly," she wrote. Advertisement Zwick was unable to meet the man in person before departing the plane, but offered her gratitude in the Facebook post, adding she and her daughter would "pay it forward." "Thank you. Not just for the seat itself but for noticing. For seeing us and realizing that maybe things are not always easy. For deciding you wanted to show a random act of kindness to US. It reminded me how much good there is in this world," Zwick wrote. She later told Yahoo someone was able to reach out to the man and put them in contact after the post went viral. "I guess it was his birthday, and he did reach out to us," she said. "He was thanking me for a birthday to remember. It was the best day. He said it made him and his wife cry, and he said, 'I am so glad we were on the same flight.'" Read More Man learns of wife's pregnancy from pilot's announcement JetBlue crew comes to rescue of bulldog with breathing issues Woman switches seats on plane, chronicles love connection