Stephanie Madoff Mack, widow of Bernie Madoff's son, Mark, spoke with ABC News in a 20/20 interview and said that if she ran into her former father-in-law she would spit in his face.

The interview will air on Friday.

I would tell him that I hold him fully responsible for killing my husband, she said in an interview clip posted on ABC News' Web site. And I'd spit in his face.

ABC News noted that she is the first member of the Madoff family to speak publicly after the financial scandal.

Mack's husband, Mark Madoff, was his father's firstborn of two sons. He committed suicide in his family's Soho apartment in December of 2010, two years after his father was arrested. He hung himself using a dog leash while his and Mack's 2-year-old son slept in a different room.

Mack and their daughter were out of town when it happened.

Mark was an innocent victim of his father's monstrous crime, who succumbed to two years of unrelenting pressure from false accusations and innuendo, attorney Martin Flumenbaum said in a statement after the suicide. We are all deeply saddened by this shocking turn of events.

Mack is coming out with a memoir about her time with the Madoff family.

The End Of Normal: A Wife's Anguish, A Widow's New Life will be released on Oct. 20.

It is being published by Blue Rider Press, an imprint of Penguin.

Left to raise her children as a single mother, Stephanie wrote this memoir to give them a sense of who their father really was, defend his innocence, and put her personal statement on record once and for all, the book's description reads on the Penguin Web site. In this candid insider account, she talks about her idyllic wedding to Mark on Nantucket, what it was really like to be a part of the Madoff family, the build-up to Bernard's confession, and the media frenzy that followed. It is about the loss of the fairytale life she knew, adjusting to life with a man she hardly recognized anymore, and the tragic and final loss of her husband.