It was a quiet and intimate moment between a grieving husband and father, and his dying newborn son. But it was captured by a friend, who posted it to Youtube, where in the past week almost 15 million people have watched it, responding with a massive outpouring of sympathy that took Chris Picco completely by surprise.

In the video Picco, a Christian worship leader, quietly plays his guitar, singing The Beatles’ famous song Blackbird, while his tiny son lies quietly, swaddled in blankets, inside a hospital incubator.

His voice is low, but firm and sweet, barely betraying the fact that only days before he had said his final and unexpected goodbyes to his wife, who died during an emergency C-section, and that he was now saying his final goodbyes to his premature son. 

Picco’s son, Lennon, named after the lead singer of The Beatles, was born premature at 24 weeks. He fought for his life for four days, at times providing hope that he would pull through, but passed away on November 12.

He told NBC News that he remembered how his wife, Ashley, would ask him to get his guitar and play for their son while he was in utero.

“So I thought, I'm going to get my guitar; Ashley would want me to sing to my son and play to my son,” he said.

“Dear friends, family, and supporters; it is with an unbelievably heavy heart that I write this,” Picco wrote on a fundraising page set up by friends the day his son died. “My little fighter, Lennon James Picco went to sleep in his daddy's arms late last night.

“He was surrounded by family, friends, and the best doctors, nurses and hospital staff in the world. He was dressed in an outfit that Ashley bought for him, with little guitars on it, and wrapped in a blanket made by a dear friend. I am so thankful for the four unforgettable days I got to spend with him.

“His mommy would have been so beyond joy to see him and to hold him, touch him, bathe him, sing to him – as I have had the privilege of doing. I have been so blessed and honored to love him before he was formed, to cherish him while mommy carried him, meet him face to precious face, and hold his perfect little body while we said ‘goodbye for now.’”