Article continues below advertisementInvestigators searching for Savannah Guthrie's missing mom are focusing on a recently vacant home near where the 84-year-old was last seen. During the Tuesday, March 17, episode of reporter Brian Entin's YouTube show, he revealed, "There's one neighbor that moved out before Nancy [Guthrie] disappeared, and they [FBI agents] are asking more questions about that situation."Following the update, retired SWAT commander Bob Krygier suggested the suspect(s) may have used the vacant property to watch Nancy, who vanished from her Tucson, Ariz.