While Howard Serena was away fighting in World War II, his wife Laura often sang to herself to cope with his absence. Her ballad of choice was “You’ll Never Know,” a yearning melody that cabaret crooner Rosemary Clooney once performed with Harry James.

Everyone told Laura that she had a voice just like Clooney’s. “You’ll never know just how much I miss you,” the song goes. “You’ll never know just how much I care.”

Nine kids and 73 years of marriage later, Laura, 93, is the one getting ready to depart, and Howard is singing the song back to her.

A video posted to Facebook and YouTube of the 92-year-old Floridian’s hospice bedside performance has garnered over 6 million views since it was uploaded this weekend. The footage, filmed by granddaughter Erin Solari, is deeply touching: It shows Howard leaning towards his dying wife, telling her he loves her before breaking into song.

“You went away and my heart went with you,” Howard sings as he strokes Laura’s face. “I speak your name in my every prayer.”

Though he is hard of hearing and she’s lost almost all of her vision, their eyes remained on each other as they exchanged loving words.

Romantic gestures like these are commonplace in their large family, Solari told The Washington Post. “Music and love and laughter is what our family is about,” she said, adding that her mother — “the family DJ” — had her boombox cued up to “You’ll Never Know” because it has become her grandparents’ signature song over the years.

At their 50th anniversary celebration, the Serenas performed it as a duet after renewing their vows. This recent performance was prompted by Laura’s request to hold her husband in her final days.

“I was your best lover,” Howard told his wife with a smile. “I don’t know how many others you had, but I was the best.”

“Oh, I know it!” Laura responded hoarsely.

According to Solari, the response to the video has been overwhelming. “Most people are in shock or awe,” she said. “They wonder, ‘Why would someone share such a private moment?'”

But her family has never been very private. Rather, she describes them as a “rowdy” crowd that often makes their presence known. This has certainly been the case with this video, which has moved well-wishers to flood Solari’s inbox.

Solari partially credits the support the family has received from strangers with lifting their collective spirits — so much so that Laura has been well enough to return to her Gainesville, Fla., home, where they hope she will pass peacefully. And while Howard suffers from severe dementia, Solari said he has recently been “awfully lucid.”

Her grandfather, who can’t stand up on his own, is held up by Solari’s physical therapist cousin throughout the video. When the song ends, the couple shares a kiss.

“You’re mine,” Howard sniffs as he slowly settles back into his wheelchair. “You’re mine.”

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