The country world is mourning after Kris Kristofferson died on Saturday (Sept. 28) at 88 years old. Whether you knew him best as a world-class songwriter, one-fourth of the legendary group The Highwaymen, a solo artist or for his work as a film actor, Kristofferson left an indelible impact on the entertainment industry, and its stars quickly began to take to social media to pay their respects.