07/07/2010 05:12 am ET Updated May 25, 2011

Roxanne Marshall, Rielle Hunter's Sister, Slams Her And Supports Elizabeth Edwards

Rielle Hunter's sister, Roxanne Marshall, says her entire family was "pretty upset" that Hunter hasn't apologized to Elizabeth Edwards for her affair with John Edwards, according to excerpts from an interview airing Friday night on "Extra."

"We were hoping she would own up to some of the things she did," Marshall, who says she and Hunter were close growing up but have since become estranged, told the "Extra" crew. "They were married, she has cancer. She has two little children. She deserves some respect."

Hunter's appearance on Oprah was a prime opportunity to apologize, Marshall said, and she should have taken it. "She just chose to take another path, and I don't know who she is," Marshall said. "She's crossed over a boundary none of us would ever even think about."

Had Oprah given her such a chance, Marshall likely would have taken it. "I would like to tell Mrs. Edwards that I feel so bad about the whole situation, and in my heart, I feel for her," she told "Extra."