Four letters sent from JFK to the family of Harold W Marney, a crewmember killed in action aboard the PT-109 boat he commanded during the second world war, will feature in RR Auction's sale of presidential memorabilia.
The lot is available with a minimum bid of $10,000 from September 11-17.
Kennedy writes: "This letter is to offer my deepest sympathy to you for the loss of your son. I realize that there is nothing that I can say can make your sorrow less; particularly as I know him; and I know what a great loss he must be to you and your family.
"Your son rode the PT 109 with me on the night of August 1-2 when a Japanese destroyer, travelling at a high speed cut us in two, as we turned into him for a shot.
"I am truly sorry that I cannot offer you hope that he survived that night. You do have the consolation of knowing that your son died in the service of his country."
The incident happened off the coast of the Solomon Islands in the South Pacific in August 1943. The surviving crew managed to swim to the relative safety of nearby Plum Pudding Island, with Kennedy famously using his teeth to tow an injured colleague.
Three of the letters date to between 1943-1944, while the last was sent in 1961 - a year into Kennedy's office.
It reads in part: "I recently requested from the American Battle Monuments Commission a picture of the Manila American Cemetery, whose memorial wall bears the inscription of your son and my former shipmate."
We have this stunning photograph signed by Kennedy and his family, just one year before his assassination.
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