"It's one thing writing it, but then realizing that people are going to really, really know you... I figured if I'm going to do this, I am going to be really honest about it," Dean said.
On Fox Nation's "Dana Perino's Book Club," Dean explained that writing the book wasn't easy, because it is deeply personal. In "Mostly Sunny", Dean opens up about her upbringing, family struggles, her career path and the hurdles she faced along the way. She compared the writing experience to, "jumping off a diving board."
Perino mentioned one chapter that particularly stood out to her, in which Dean wrote about her battle with multiple sclerosis and her decade-long fight with the debilitating disease.
"Getting a diagnosis of MS was very dark... and all I was looking for were books of people that I could look to, who was still thriving and doing okay. I wanted some hope, some sunshine in a very cloudy dark time and there weren't many books out there," explained Dean.
Dean said it was her colleague and Fox Business host, Neal Cavuto, who gave her the strength she needed to fight the disease head-on. Cavuto, who also suffers from MS, reassured Dean that her job was safe and that Fox would do everything they could do to accommodate her.
"There are going to be tough times, but you are working at a company that will do whatever you need -- and if they need to build wheelchair ramps, they will," Dean recounts Cavuto saying.
Cavuto also joked that Dean would be exempt from chores because of the diagnosis.
"You'll always get out of taking out the garbage because you have MS," she recalled him saying.
Dean explained that she never allowed the disease to hold her back, and her optimism is evident in the bestseller.
"MS has the same initials as Mostly Sunny," said Dean, "and I take that as a sign."
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