By Hayley Peterson PUBLISHED: 08:07 EST, 29 March 2013 | UPDATED: 13:13 EST, 29 March 2013 The daughter of disgraced politician John Edwards has said she maintains a relationship with her 4-year-old half sister, who was conceived out of her father's love affair with his videographer during his bid for the 2004 Democratic presidential nomination. 'She's my sister... she's just a really sweet, innocent little girl,' Cate Edwards, 31, said of 4-year-old Quinn Hunter in an interview with NBC's Savannah Guthrie. 'I certainly think of her as part of our family.' Quinn is the daughter of John Edwards' former mistress Rielle Hunter, whom Cate said she hasn't seen in years. Hunter has recently published a tell-all book about her romance with the former North Carolina senator.
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Cate Edwards, 31, said she was 'devastated' and 'disappointed' when her father told her about his affair
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John Edwards' affair with Rielle Hunter, his videographer, happened during his 2004 bid for the Democratic presidential nomination
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Cate tells how her father rushed to her mother Elizabeth's bedside as she was dying of cancer, but said she's not sure if her mother ever forgave him
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Edwards is speaking out as she launches a program to help underprivileged students through a nonprofit named after her mother, the Elizabeth Edwards Foundation, in Raleigh
In her book 'What Really Happened: John Edwards, Our Daughter and Me', @placeholder describes the Edwards' marriage as broken by the time she arrived on the scene.