I just read of this sad news yesterday. Jonathan Sandys died on December 29, 2018 from lung disease. He was only 43 and leaves behind his wife and two young children. He co-authored the book, "God & Churchill: How the Great Leader's Sense of Divine Destiny Changed His Troubled World and Offers Hope for Ours".
https://www.christianpost.com/voice/jonathan-sandys-the-man-who-could-call-churchill-great-grandpapa-dies.html
I started on his profile on WikiTree, Jonathan Sandys