Is there anything more sweet than writing a love letter to your beloved?

In his 2012 book, 'House of Cash: The Legacies of my Father, Johnny Cash,' John Carter Cash published a series of letters penned by his late father, Johnny Cash, to his late mother, June Carter Cash. Within the sweet notes, the country icon lovingly referred to his wife as “Princess” and insisted she was the greatest woman he’d ever met.

"We get old and get use to each other. We think alike. We read each others minds. We know what the other wants without asking. Sometimes we irritate each other a little bit. Maybe sometimes take each other for granted," Johnny — who passed away at age 71 in 2003 — began a 1994 letter to June on her 65th birthday.

johnny cash love letter 1
'House of Cash'

"But once in awhile, like today, I meditate on it and realize how lucky I am to share my life with the greatest woman I ever met. You still fascinate and inspire me. You influence me for the better. You’re the object of my desire, the #1 Earthly reason for my existence. I love you very much. Happy Birthday Princess," he wrote.

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In a second letter, the singer affectionately referenced his hit song, "Ring of Fire," to describe his relationship with June.

"That's really nice June. You've got a way with words and a way with me as well. The fire and excitement may be gone now that we don't go out there and sing them anymore, but the ring of fire still burns around you and I, keeping our love hotter than a pepper sprout," he wrote.

johnny cash love letter 2
'House of Cash'

Johnny and June married on March 1, 1968. They welcomed their only child, a son named John Carter Cash, in March 1970. June died in May 2003 just four months before her husband too passed away that September.

h/t 'Buzzfeed'