MONROEVILLE, Ala. — Retrace the tangled legal saga of Harper Lee and her legacy, “To Kill a Mockingbird,” and a pivotal moment emerges.

Right after Lee’s longtime protector, older sister and attorney, Alice Finch Lee, turned 100 and stopped practicing law a couple of years ago, another lawyer in her small firm became the point person for the “Mockingbird” brand.

When Tonja Carter became Alice Lee’s law partner after working in her office for years, she soon became known for jealously protecting the writer from visitors and perceived threats to her business interests.

And it was Carter who was the lynchpin in the stunning Feb. 3 announcement that a sequel to “Mockingbird” titled “Go Set a Watchman” would be released, according to an arm of HarperCollins Publishers. She found the unpublished novel, written in the mid-1950s but locked away since, and negotiated the deal, the publisher said.

The news was baffling to many. The intensely private author, known locally by her first name of Nelle, had told friends and relatives for years that she didn’t plan to publish another book. Speculation quickly swirled over whether the 88-year-old writer’s wishes are being honored, particularly after friends said she had behaved erratically at her sister’s funeral in November.

But others close to Carter and the Lee sisters cautioned against misreading Carter’s legal maneuvering.

“She’s not some interloper,” said Connie Baggett, who got to know Carter and the Lees during her decades covering southwest Alabama for the Mobile Press-Register. “She’s been part of the inner circle for years.”

Harper Lee is nearly blind and deaf, and lives in an assisted living center. She was last seen publicly at her sister’s funeral, where she talked loudly to herself about seemingly unrelated things in a manner that alarmed other mourners, according to three people who were there.

But historian Wayne Flynt said he visited his longtime friend the day before the deal was announced and found Lee completely lucid. While she didn’t mention her own new book, she was cracking jokes and discussing the works of C.S. Lewis, he said.

“This narrative of senility, exploitation of this helpless little old lady, is just hogwash. It’s just complete bunk,” Flynt said.

Carter, 49, hasn’t responded to interview requests, but she defended her actions in a series of text messages and emails to The New York Times, the newspaper reported Sunday.

Lee is “extremely hurt and humiliated” at the idea that she’s been taken advantage of, Carter wrote. “She is a very strong, independent and wise woman who should be enjoying the discovery of her long lost novel. … Instead, she is having to defend her own credibility and decision making,” the Times reported.

“I’m alive and kicking and happy as hell with the reactions of ‘Watchman,'” the author said Thursday in another statement Carter relayed.

“Watchman” will be released in July and already is No. 1 on Amazon based on pre-orders, sure to build on the phenomenal success of “Mockingbird,” which has sold millions of copies since winning Lee the 1961 Pulitzer Prize.

With Carter as her lawyer, Lee sued the son-in-law of a former literary agent in May 2013, regaining her copyright. Then she sued a museum in her hometown for selling “Mockingbird” souvenirs, which it had done for years. Baggett said Carter had advocated a more aggressive response to a proliferation of “Mockingbird”-related products.

“Nelle was fiercely protective of the characters in her book while Alice was handling things,” Baggett said. “As things have unfolded, Tonja took action. I can’t imagine anyone looking out for the interests of the book and for Nelle who wouldn’t do the same.”

Then Marja Mills, the sisters’ neighbor, published “The Mockingbird Next Door: Life with Harper Lee,” and Carter released a statement attributed to the author saying the book wasn’t authorized.

Alice Lee apologized in a handwritten letter to Mills, explaining that Carter had created the statement and had Harper Lee sign it. “Poor Nelle Lee can’t see and can’t hear and will sign anything put before her by anyone in whom she has confidence,” Alice Lee wrote in May 2011.

“I am humiliated, embarrassed and upset about the suggestion of lack of integrity at my office” that Carter created, Alice Lee added in the letter.

Alice Lee died Nov. 17 at 103. It was also last fall, the publisher said, when Carter found the “Watchman” manuscript.