Howard and Laura were married for 73 years. They loved each other, saw each other through a world war, and raised children and grandchildren together.

When Laura was near the end of her life, unable to see and on her deathbed, Howard decided to sing her their song just one last time.

His grandchildren caught the emotional moment on camera and uploaded it to YouTube, giving millions of well-wishers a first hand look at true love.

According to their granddaughter, Erin Solari, the song Howard sings to his dying wife was an integral part of their marriage and the history of their family.

The song "You'll Never Know," as performed by Rosemary Clooney, was a comforting presence for the two when Howard went off to fight in World War II.

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“Howard (Grandpa) is singing to her their love song, the song that comforted her when he went away to fight in World War II,”Solis explains.

“At family gatherings, it was not uncommon for the two of them to sing this song together, each taking a verse and serenading the other. In fact, after fifty years of marriage, they renewed their vows and performed this song as a duet for the entire family at the reception.”

The video itself is a crash course in true love, as Howard struggles to stand and hold his wife, and Laura tries with all her strength to sing along.

Since the video was posted, Laura Virginia has been able to leave hospice and is now resting peacefully at home, surrounded by her friends and family, engrossed in their love.