Nick Harvey's father had been demented and hospitalized, so he had not been in his son's home in East Sussex, England, all year.
But on Sunday, Harvey invited his father for lunch. When he arrived, 79-year-old Paul Harvey went straight to the piano.
"It's like a magnet for him – he's made of music," said Nick Harvey in a written interview with The Washington Post.
The piano of his son, Paul Harvey, a former composer and concert pianist, first played a classical piece. Nick Harvey recorded it on his phone.
"I did not know how many chances I would have to keep him playing that way," said Nick Harvey, who is also a composer and writes music for British television programs.
Then Nick Harvey asked his father to play "Where's the Sunshine," a piece Paul Harvey composed in the 1980s as music director of a British secondary school. Nick Harvey said that, like many of the other songs his father wrote for school productions, "it might have been good enough for the West End stage."
Nick Harvey was not sure if his father would remember. This is also evident in the video in which Paul Harvey was not sure.
In the video, he hesitates when he starts, and then confidently and fluently plays the composition he wrote decades before. His son posted it on Twitter. Within a day, it was viewed more than 2 million times. Tens of thousands of people responded with awe and admiration. Celebrities such as James Corden and British singer Emeli Sandé tweeted it again.