The CNN journalist shared a slideshow of photos of his mom over the years, including one where he is presumably holding her hand shortly before her death.
"In the end, after all else is stripped away, there is only love," he wrote. "My mom believed in love more than anyone. It was her guide, her solace, it's what drove her, and in her final moments, it is what surrounded her. 'i love you, you know that,' she would say to me, and i did, i knew it from the moment i was born, and i will know it till the moment i die. It was her greatest gift to me."
On Monday, Cooper revealed on CNN his mother died after having been diagnosed with stomach cancer earlier this month. A socialite, painter and actress, Vanderbilt was also known for her romantic relationships, including those with Frank Sinatra and director Sidney Lumet. She would marry four times in her life. In the early 1980s, her brand of tight-fitting jeans became a fashion staple for many.
Vanderbilt had four sons. She witnessed one of her younger sons, Carter, take his own life when he was just 23 years old.
"Love is what she believed in more than anything," Cooper said on CNN, prefacing his comments on Instagram.
"Gloria Vanderbilt was an extraordinary woman, who loved life, and lived it on her own terms," he said in a statement. "She was a painter, a writer, and designer but also a remarkable mother, wife, and friend. She was 95 years old, but ask anyone close to her, and they'd tell you, she was the youngest person they knew, the coolest, and most modern."