The family of missing 84-year-old Nancy Guthrie have offered $1m for her recovery.
NBC Today show co-host Savannah Guthrie said on Instagram that "someone knows how to find our mom and bring her home" on Tuesday, and urged people to keep Ms Guthrie in their thoughts.
The 84-year-old went missing more than three weeks ago after she failed to appear at church on 1 February.
She was last seen at her home in Tucson, Arizona, on the evening of 31 January. Authorities believe she was kidnapped, or otherwise taken against her will.
The TV presenter, who co-anchors the morning programme on Sky's US partner network, said in the video: "Please keep praying without ceasing. We still believe. We still believe in a miracle.
"We still believe that she can come home, hope against hope, as my sister says. We are blowing on the embers of hope.
"We also know that she may be lost. She may already be gone."
The Instagram post says that the family offers its reward on terms consistent with the FBI's criteria for payment of its reward in this case.
The bureau is separately offering a $100,000 reward for any information that leads to Ms Guthrie or to an arrest.
In a post on X, the FBI's office in Phoenix said anyone with "firsthand knowledge" of the missing woman's whereabouts should contact its tip line.
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Several hundred people are working on the investigation into Ms Guthrie's whereabouts, the Pima County Sheriff's Department has said, and more than 20,000 tips have been received.
Authorities have not yet identified a suspect in the case, and said this month that her family are not being investigated.
Pima County Sheriff Chris Nanos said: "To suggest otherwise is not only wrong, it is cruel. The Guthrie family are victims plain and simple."
The FBI had previously released doorbell camera images and videos of an armed and masked man outside Ms Guthrie's house on the morning she disappeared.
Two law enforcement sources told Sky News' US partner NBC News on Monday that one of the images shared was captured earlier, which the sheriff's office denies.
(c) Sky News 2026: Family of Nancy Guthrie offer $1m reward for her recovery
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