The author of a tell-all book about the downfall of former U.S. senator John Edwards, says he is surprised that the mistress of his former boss has chosen to speak about her lifestyle to a major U.S. magazine, when she has already been in the limelight for unfavourable reasons.

Andrew Young spoke to CTV's Canada AM on Wednesday morning, expressing surprise about the recent appearance of Rielle Hunter in GQ magazine and discussing his controversial decision to pretend to be the father of the child that his former boss conceived with his mistress.

Young's book, The Politician, attempts to explain why he helped Edwards keep secret the fact he conceived a baby with Hunter -- the mistress who the one-time presidential candidate hired to made videos for his campaign in 2006.

Young, the long-time aide to the former senator, said he'd been working for Edwards for 10 years when he was asked to say he was the father of Hunter's child.

The two had grown very close over that time and Young said the stakes were high when the request was made -- Edwards' wife had been diagnosed with cancer and he had been gaining in the polls in his quest to become the Democratic candidate for the presidency.

"He was one of my best friends, we jogged together, our kids played together," Young said during an interview from Raleigh, N.C., on Wednesday morning.

Then came the question that has made Young a household name and the author of his tell-all book.

"The gist of his question was: My wife, Elizabeth, is about to die of cancer in the next three to four weeks, and will you please do this for me before she dies," said Young.

"It wasn't quite as simple as: ‘Will you take the fall for me?'"

It would be more than two years before Edwards admitted that he was the father of Frances Quinn Hunter, which he publicly acknowledged for the first time in January.

But Young said that he doesn't regret all of the time he spent working for Edwards.

Especially in the early years before Edwards set his eye on the presidency.

"The first six years I worked with John Edwards, he was an incredibly awesome, inspiring person to work for. You truly believed that you were a part of history," Young said.

"After the 2004 election, after he and (John) Kerry lost, his ego got the best of him and he changed substantially. I don't regret the first five or six years, I do regret the rest of it."

Hunter currently appears in a revealing photo spread GQ, in which she is pictured posing with her young daughter and among children's toys.

In an interview with the magazine, Hunter says she was "not the home wrecker" in the marriage of John and Elizabeth Edwards, who are now formally separated.

Reacting to the GQ interview, Young said he was "surprised by the tone and the graphics" that were used in the magazine piece, including the suggestive photos of Hunter which he said "was more of a Jennifer Aniston shot than it was anything else."

Young said that he preferred to tell his story in his own words in The Politician, rather than speak through a reporter.

"That was one of the reasons that I wrote a book," he said.

"Because when you hand it over to a magazine, you let them define for you what it is that you're presenting."

Hunter has sued Young for invasion of privacy in a case that is still before the courts and involves a sex tape that reportedly involves footage of Edwards and Hunter.

With files from The Associated Press