Nancy Sinatra is remembering Elvis Presley nearly five decades after the legendary singer's death.Marking the anniversary of the Heartbreak Hotel crooner's passing, Nancy Sinatra shared a heartfelt tribute describing her former Speedway co-star as both deeply funny and intensely sensitive."Elvis was extremely sensitive. He had the biggest heart. He felt everything. Beneath the fame was a man who was deeply affected by the world around him and by the people he loved. That tender, caring side of him is something I will never forget."Nancy Sinatra recalled how Elvis Presley could quickly shift from making her laugh with a joke to having serious late-night conversations about troubling stories he had seen on the news."Elvis was both the funniest person and the most serious person I ever knew. One minute, he could have me laughing with some silly joke, and the next, he would be on the phone late at night, talking about a terrible story he had seen on the news."She also remembered his compassionate nature, describing him as a man with a huge heart who was deeply affected by the people and world around him.Nancy Sinatra recalls friendship and fun memories with Elvis Presley on set of SpeedwayAlongside her message, the These Boots Are Made for Walkin' singer accompanied her tribute with a picture that she claimed was her favorite, featuring herself and Elvis Presley, saying it captured the happiness and affection they shared while working together."This is my favorite photo of us because it captures the joy and affection we shared. We had so much fun making Speedway!"Nancy And Frank Sinatra Talk To Elvis - Source: GettyThe pair starred opposite each other in the 1968 musical comedy Speedway. Nancy Sinatra talked about the friendly rapport between her and Presley on the studio set and mentioned the bicycle that Elvis Presley built for her."Elvis had a tandem bike made, and we would ride it around the studio lot, much to the chagrin of the studio heads, occasionally even popping up on a studio tour. We were like The Katzenjammer Kids!"According to Nancy Sinatra, the two would ride around the lot together and occasionally even appear on studio tours, much to the annoyance of studio executives.Reflecting on their antics, she compared them to the mischievous comic-strip characters, the Katzenjammer Kids.Elvis Presley On Stage - Source: GettySinatra ended her tribute with a message to Presley, saying she continues to love and miss him and keeps him in her heart."I love and miss you, EP. You are always on my mind and forever in my heart."Presley died on Aug. 16, 1977, at age 42. His death continues to be remembered annually by fans and those who knew him personally.