Jean Simmons and Laurence Harvey sing carols with Danny Kaye on his Christmas TV special, 1965
One of my father’s great joys was singing. “I’m crazy about being a group singer,” he used to say. On one of his CBS shows with the great Ella Fitzgerald, he was a group of two. He practiced so he could spontaneously scat with her. You could feel his abandon when he did up-tempo songs, and his tenderness when he sang ballads.
[ - Dena Kaye, source - AARP.org]