the blood of slaves and slave owners. >> joining us live, msnbc chief washington correspondent, norah o'donnell. it is an incredible story, norah. 168 years after melvi inform ia valued at $475 gets sold to the property of another human being, you have mrs. obama living in the white house. >> it is extraordinary. these are details about the first lady's family history that even she did not know about. so, this fills in some of the bla blanks. it also substantiates some reports that she did have a white ancestor. so, they know that now. so, it's truly extraordinary and says a lot about this journey. and the authors of this piece in "the new york times," as i spoke with them yesterday, as they pointed out, it's not that this is such an extraordinary tale about african-americans in this country, it's actually more ordinary. this is, in part, the legacy of many african-americans in this country. so it's remarkable. the first lady also is not