Savannah Guthrie appealed to her mother\u0027s alleged kidnappers to "do the right thing" on Monday, saying in a new video message that her family has been living in a "nightmare that will not end."In her Instagram post, the "Today" show host said her family had "done our part" and would "never stop looking for" their 84-year-old mother, Nancy Guthrie, who has been missing since February."The world can be a cruel and unforgiving place, and I know that you have tried to do things the right way," Savannah Guthrie said. "So I am asking you, begging you, to do the right thing now."She captioned the post: "bring her home."Monday\u0027s post marks the Guthrie family\u0027s first major public appeal regarding her mother since June 23, when Savannah Guthrie gave a teary address during her NBC show from the anchor desk.Nancy Guthrie was reported missing on Sunday, Feb.1, after not showing up for church. The sheriff said at the time that it appeared she was abducted from her home in Tucson, Arizona. Two ransom notes\u00a0were addressed to the Guthrie family days after her disappearance, including a note that said she had died, according to authorities who believe they were likely sent by the person or group of people who abducted her.The\u00a0first note\u00a0demanded millions\u00a0in bitcoin\u00a0for Nancy Guthrie\u0027s release. In the second note, sent a few days later, the apparent abductors revealed that she had died. The note indicated that they did not mean for her to die, according to sources who reviewed the notes.