Rosie O'Donnell reveals details of her unusual relationship with a viewer who had a multiple personality disorder in the second of her two-part interview with Diane Sawyer airing tonight.

O'Donnell says she sheltered a woman who had contacted her, claiming her 14-year-old daughter had been attacked and impregnated by her minister. 

There was only one problem  the woman, who lived in a trailer in Oregon, didn't have a daughter. 

"I have a very soft spot for kids who are in trouble or in pain," O'Donnell says. "And it was a mother calling for her daughter. And so when I saw this mother caring about her daughter in the way she did, it hooked me in some way." 

O'Donnell says she offered to let the woman's teenaged daughter live in her apartment while she was away for the summer. 

But she was shocked to learn that the daughter didn't exist — and that the woman suffered from multiple personality disorder. 

O'Donnell says she wasn't put off by the woman's illness — in fact, she says she identified with her. 

"I felt like her, and that's what's hard for people to understand, because they see Rosie O'Donnell on TV and they think, well, what would you have in common with a crazy woman who lives in Oregon in a trailer? 

"We both had hard childhoods. We both had interesting ways of coping by becoming other people. 

"But you know I did that, too. I do that when I'm Rosie O'Donnell, comedienne  it's show time." 

Rosie's interview, which airs tonight at 10 on Ch. 7 on Primetime Thursday, is to publicize her autobiography, Find Me.

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