Kate, 49, said this in an Instagram post to mourn the musician who died at the age of 44 after battling Angioimmunoblastic T-Cell Lymphoma.
The disease is a rare form of non-Hodgkin lymphoma, which is a group of related cancers that affect the lymphatic system (lymphomas).
Kate shared a video of Sound Sultan advertising her event in 2020.
“I have never called on you that you have said No to my request and vice versa,” she wrote.
“You show up every blessed time and on time too!! I know Allah will receive you because you gave of yourself every single time, no questions asked.
“MY ANCESTOR, we joked about how you never aged a day all these years … Rest on my dear friend and brother.”
Sound Sultan left behind a wife Farida, three children and siblings.