According to a new book out on May 2 from her longtime friend and confidante, Harper Lee called Truman Capote a "compulsive l[iar]" in her letters. Lee and Capote were friends and writing partners for years, and it's widely known that Lee based the To Kill a Mockingbird character Dill Harris on the In Cold Blood author. Lee's revelation about Capote's lying habit comes from a March 2006 letter to Wayne Flynt, one of many contained in Flynt's forthcoming Mockingbird Songs: My Friendship with Harper Lee. 
 
 Both Lee and Capote achieved literary success in the mid-20th century. Following the sensational Clutter murders in 1959, the two writers traveled to Kansas so that Capote could cover the story for The New Yorker. Lee worked as Capote's "assistant researchist" in Kansas, and later edited his final draft of In Cold Blood. She also published her own article about the murders in the March 1960 issue of the FBI trade magazine Grapevine. But when he published In Cold Blood in 1966, Capote gave Lee no credit for her hard work. 
 
 Lee's letters to Flynt reveal a reason for Capote's snub. After writing that "Capote’s drinking and misery soured their friendship," according to The New York Times, Lee told Flynt: "I was his oldest friend, and I did something Truman could not forgive: I wrote a novel that sold . . . He nursed his envy for more than 20 years." 
 
 Read all about Truman Capote's "compulsive lying" and more when Mockingbird Songs comes out on May 2. ||||| Wayne Flynt was a close friend of Harper Lee until her death in 2016, one of the few she still granted visits after she entered a nursing home near the end of her life. Before that, Flynt, professor emeritus of history at Auburn University and author of numerous books on Alabama history, corresponded with Lee through letters since their initial meeting in 1983. 
 
 With a sure-to-be bestseller on the Pulitzer Prize-winning author of "To Kill a Mockingbird" debuting Tuesday, author Wayne Flynt discussed Harper Lee in an exclusive interview with the New York Times. 
 
 Flynt's book, "Mockingbird Songs: My Friendship With Harper Lee" offers insight into the famously publicity shy Lee, including some confirmations of much-discussed topics such as her relationship with Truman Capote and if she would have approved of this book. 
 
 Release date set for Wayne Flynt's book on friendship with Harper Lee 
 
 Here are just a few of the things we learned from the in-depth interview: 
 
 1. Lee, known in her hometown of Monroeville by her given name of Nelle Harper Lee, only asked Flynt not to write about her while she was living. Flynt told the NYT he feels the book "allows her to speak beyond the grave and without any risk to her privacy." 
 
 2. One reason Lee shied away from the media and the glare of fame's spotlight was her fear of obsessive fans. She once had a stalker and was concerned with stalkers and assassination, Flynt told the NYT. 
 
 3. Truman Capote was a compulsive liar. Lee and Capote were childhood friends in Monroeville and he was the inspiration for the character Dill in "To Kill a Mockingbird." Lee's friendship with Capote eventually ended over jealousy. Lee wrote to Flynt: "I did something Truman could not forgive: I wrote a novel that sold." 
 
 Click here to read Flynt's Eulogy for Harper Lee: 'Atticus' Vision of Ourselves' 
 
 4. Lee was so nervous before interviews and speaking engagements that she would vomit. 
 
 5. Flynt admits Lee "may not have fully participated in the decision to publish a long forgotten and flawed first novel ('Go Set a Watchman')" because of her age and health issues. However, Flynt said that at the time, Lee welcomed its publication. 
 
 Click here to read the detailed interview in the New York Times.
– In the soon-to-be published contents of a decade-old letter, Harper Lee accused her "oldest friend," Truman Capote, of being an inveterate liar who destroyed their friendship with his jealousy. Wayne Flynt, an Alabama historian and longtime friend of Lee's in his own right, is publishing a book next week about his quarter-century relationship with the To Kill a Mockingbird author, the New York Times reports. According to AL.com, Flynt was one of a handful of people still allowed to visit Lee after she moved into a nursing home in the final years of her life. Flynt tells the Times that Lee, who removed herself from public life in the 1960s, only told him not to write about her while she was alive. Capote and Lee had been writing partners for years, and she even based a character in To Kill a Mockingbird on him, Bustle reports. But in a 2006 letter to Flynt, Lee said of Capote: "His compulsive lying was like this: If you said, 'Did you know JFK was shot?' He'd easily answer, 'Yes, I was driving the car he was riding in.'" She also said that while their friendship was strained by Capote's drinking and "misery," it was ultimately ruined by jealousy. "I did something Truman could not forgive: I wrote a novel that sold," she wrote. "He nursed his envy for more than 20 years." To Kill a Mockingbird has sold more than 40 million copies. Flynt's Mockingbird Songs: My Friendship With Harper Lee will be released May 2.