Savannah Guthrie makes urgent plea in search for her missing mother: ‘It is never too late to do the right thing’

• Savannah Guthrie has issued a plea for her elderly mother's release in a new video on Instagram.
• She said her family "still have hope" and said "it is never too late to do the right thing."
• Her 84-year-old mother, Nancy Guthrie, has been missing since February 1.

"Today" show host Savannah Guthrie has posted a video pleading for her mother's release, urging anyone involved in her disappearance that "it is never too late to do the right thing."

"I wanted to say to whoever has her, or knows where she is, that it's never too late," Guthrie said in the new video uploaded on her Instagram on Sunday.

"You're not lost or alone. And it is never too late to do the right thing. And we are here," she continued. "We believe in the essential goodness of every human being."

Nancy Guthrie, 84, was reported missing on February 1, after she was last seen the night before when her family dropped her off at home following a dinner.

Authorities have said that they believe Nancy Guthrie, who has limited mobility and relies on daily medication for a heart condition, was taken from her home just outside Tucson in Arizona.

Savannah Guthrie captioned Sunday's video: "bring her home. it's never too late to do the next right thing."

"We still have hope," the younger Guthrie said in the video.

Her family have posted several pleas for help since Nancy Guthrie's disappearance.

"We are at an hour of desperation, and we need your help," Savannah Guthrie said a video last Monday, urging the public to report anything that seemed strange to the authorities.

The FBI has increased the reward for information about Guthrie's disappearance from $50,000 to $100,000.

Savannah Guthrie has not appeared on "Today" since her mother's disappearance.