File photo of the Apollo 11 Lunar Module ascent stage
File photo of the Apollo 11 Lunar Module ascent stage Reuters

After landing on the moon on July 20, 1969, astronaut Neil Armstrong expressed his utmost excitement and delivered his iconic sentence, "That is one small step for man, one giant leap for mankind." However, many people do not know about Neil Armstrong's journey that finally made him the first human to land on the lunar surface.

In the initial phase of his career, Neil Armstrong had worked as a test pilot at the National Advisory Committee for Aeronautics (NACA) High-Speed Flight Station at Edwards Air Force Base in California. Armstrong married Janet Sharon during this time, and they had three children, Eric, Mark, and Karen.

The family was leading a happy life until the day Armstrong's only Karen was diagnosed with a malignant tumour on her brain in 1961. A year later, she passed away, and it pulled Neil Armstrong to a state of shock.

In the upcoming movie, 'Armstrong', Janet Sharon shared Armstrong's mindset after the untimely death of their daughter.

"When Neil was still working in the Air Force Karen developed a tumour in her brain before she was three. Neil missed her dearly. After Karen died I was ready to go anywhere, I thought a change would be good. Neil finally decided he would try for this space program and they accepted," said Janet in the docufilm, Express.co.uk reports.

Armstrong later applied for Project Gemini, and finally became an astronaut in the Apollo program. During his tough times, Armstrong always believed that the best way to overcome his issues was to continue the work rigorously.

"I thought the best thing for me to do in this situation was to continue with my work. Keep things as normal as I could and try as hard as I could to not have it affect my ability to do useful things," Armstrong said as quoted in the film.