So-called "Doomsday Mom" Lori Vallow Daybell, who is representing herself in the murder conspiracy trial of her fourth husband, is shaking up the courtroom with fiery exchanges during testimony.

Lori Daybell is representing herself in the Arizona trial. The brother of Lori Daybell, the mother convicted of murdering two of her children in a so-called doomsday plot, took the stand on ...