Channeling the voices of celebrities can be a lucrative career — one that requires empathy and discretion as well as literary chops. Zachary Crockett checks the acknowledgements. SOURCES:Valerie Frankel, ghostwriter.Madeleine Morel, President and Lead Agent of 2M Communications.Daniel Paisner, ghostwriter. RESOURCES:"Ghostwriting History: Churchill, Kennedy and the Authenticity of Authorship," by Andrew Mumford (The International History Review, 2024)."Column: How many ways can a political memoir backfire? Ask Kristi Noem," by Robin Abcarian (Los Angeles Times, 2024)."Notes from Prince Harry’s Ghostwriter," by J. R. Moehringer (The New Yorker, 2023)."Confessions of a Celebrity Ghostwriter," by Dina Gachman (Texas Monthly, 2022).