Who Is the Real Cindy McCain?

The potential first lady had two half sisters and battled drug addiction.

Oct. 30, 2008 — -- For nearly two years Cindy McCain's family has been under a microscope -- forced to turn their lives inside out and make even their most private moments public.

Photo shoots, speeches, bus travel, handshakes, exhaustion and exhilaration have been the norm for the potential first lady.

But after all these months, the public still doesn't seem to have a clear sense of John McCain's wife.

"It's so strange for people to say she's a 'Stepford wife,' because she's actually very independent," Alicia Colon, author of a recent book about Cindy McCain, told "Good Morning America."

During her research, Colon found out something few people knew: Cindy McCain has two half sisters -- her mother's daughter Dixie Burd and her father's daughter from his first marriage, Kathleen.

Neither woman grew up with Cindy McCain, but she was much closer to her older sister Dixie who also lived in Arizona.

"For the last two years, [Dixie] had been in [a] hospice with Alzheimer's," Colon said. "Cindy was taking care of her and she recently passed away."

When she was 24, Cindy McCain crossed paths with a war hero named John McCain. Even after the two married, however, Cindy McCain's reserved nature made it hard for her to break into the political life of Washington.

"She really felt acutely that she just didn't fit in, that she wasn't welcomed," Colon said.

Rather than stay in Washington, Cindy McCain returned to Arizona to focus on raising her children. Then, she turned her attention to humanitarian aid around the world.

She has led more than 50 humanitarian missions. With her husband, she adopted a child named Bridget from Bangladesh.

And despite her near-pristine appearance, Cindy McCain struggled with drug addiction and a devastating stroke.

"There is this inner strength to her that is extraordinary," Colon said. "She, to me, is just as tough as John McCain was when he was in the POW [prisoner of war] camps. They are a match. They are much more similar than you think."