The reason Savannah Guthrie and her family raised the reward for missing mother Nancy to $1 million — it turns out there are horrifying details unfolding behind the scenes of this case.

PEOPLE has learned new details about the decision by Nancy Guthrie’s family to offer an additional reward for information regarding her disappearance.

On Tuesday, Feb. 24, Savannah Guthrie announced that she and her siblings are offering “up to $1 million” for the recovery of her 84-year-old mother, with hopes that the new number incentivizes those who have been reluctant to come forward to share what they know. The FBI’s reward of $100,000 also remains active.

A source close to the family tells PEOPLE, “The family first raised this on the first day of the investigation and has been ready to do this ever since. They were advised by all involved in the investigation that doing so earlier might overwhelm the infrastructure set up to field leads, tens of thousands of which have been coming in organically.”

PEOPLE further learned that Savannah, 54, used the language “up to $1 million” because if there is more than one valid claim, the reward may be split. The reward isn’t contingent on an arrest, and the family will continue to follow the guidance of the FBI in determining if a lead or tip warrants a payout.

In the Today host’s video, she spoke about her family’s hope that Nancy will be returned after she was “taken in the dark of night from her bed” on Feb. 1, noting that they still believe “in a miracle.”

“As my sister [Annie Guthrie] says, ‘We are blowing on the embers of hope.’”

Savannah said it’s been “agony” since her mother went missing 24 days ago. The family has been “fearing for her and aching for her and most of all just missing her.”

“We also know that she may be lost, she may already be gone,” Savannah said. “She may already have gone home to the Lord that she loves and is dancing in Heaven… and if this is what is to be, then we will accept it. But we need to know where she is. We need her to come home.”

In addition to the reward, the Guthrie family donated $500,000 to the National Center for Missing and Exploited Children.

“We also know that we are not alone in our loss. We know there are millions of families that have suffered from this uncertainty,” the NBC co-anchor said. “We hope that the attention that has been given to our mom and our family will extend to all the families like ours who are in need.”

Savannah’s message concluded with another plea, urging those with any information to contact authorities: “Please, if you hear this message; if you’ve been waiting and you haven’t been sure, let this be your sign to please come forward, tell what you know and help us bring our beloved mom home so that we can either celebrate a glorious, miraculous homecoming or we can celebrate the beautiful, brave and courageous and noble life that she has lived. Please be the light in the dark.”

Nancy and Savannah Guthrie.savannahguthrie/Instagram

Savannah’s last Instagram video was shared on Sunday, Feb. 15. In the clip, she called for “whoever has her [mom] or knows where she is” to come forward.

She also addressed Nancy’s kidnappers directly, saying: “I wanted to say to whoever has her or knows where she is that it’s never too late. And you’re not lost or alone. And it is never too late to do the right thing. And we are here. And we believe. And we believe in the essential goodness of every human being.”

“It’s never too late,” she said, writing in the caption: “Bring her home. It’s never too late to do the next right thing.”

The Pima County Sheriff’s Department and FBI have said they believe Nancy was kidnapped by an armed man seen in surveillance footage. He appeared to tamper with Nancy’s doorbell camera in the early hours of Sunday, Feb. 1. She was last seen by family the night before.

The individual, who has not been identified, is described by the FBI as a “male, approximately 5’9” – 5’10” tall, with an average build.” In the video they are wearing a “black, 25-liter ‘Ozark Trail Hiker Pack’ backpack,” according to a post by the FBI on X.

On Thursday, Feb. 19, a spokesperson for the PCSD told PEOPLE that investigators are “not ruling out that that was the only person involved” as Nancy’s whereabouts remain unknown.

In the weeks since Nancy’s disappearance, local, state and federal authorities have flooded the area, combing the rugged desert terrain for any sign of her or clues that could lead investigators to answers.

Additionally, multiple alleged ransom notes have been sent to local media stations demanding the Guthrie family pay multi-million dollar sums by a set deadlines of Feb. 5 and Feb. 9, which have since passed. It remains unclear if the family has made a payment.

The investigation has also been complicated by “mixed” DNA recovered from inside Nancy’s home. In an interview with NBC News published on Feb. 21, Pima County Sheriff Chris Nanos said that the samples contain genetic material from more than one person, making it harder for authorities to process them through databases.

Pima County Sheriff Chris Nanos; Nancy Guthrie.Jan Sonnenmair/Getty; Nathan Congleton/NBCU Photo Bank/NBCUniversal via Getty

On Feb. 23, Nanos told PEOPLE that there is “no evidence” that the masked man captured on doorbell camera footage at Nancy’s Arizona home was also caught on camera there prior to her disappearance.

Residents in Nancy’s neighborhood were previously asked by the sheriff’s department to submit surveillance footage dating back to Jan. 1, with particular focus on two windows of time between Jan. 11 at 9 p.m. and midnight, and Jan. 31 between 9:30 a.m. and 11 a.m. Authorities specifically requested video showing cars, traffic, pedestrians or anything unusual.

Nanos has shared in the past that it could take “years” to find Nancy.