The abrupt vanishing of Nancy Guthrie remains a significant concern for both law enforcement and the general public, as minimal progress has been achieved in the current investigation.Nancy Guthrie's family is offering a $1 million reward for information (REUTERS)As the purported kidnapping case approaches its fourth month, a former FBI special agent has expressed his views regarding the situation and the likelihood of a possible suspect emerging soon.Ex-FBI agent Jason Pack weighs in on Nancy Guthrie caseIn an interview with Parade, retired FBI agent Jason Pack articulated that when a case remains unresolved for an extended period, many people tend to label it as “cold.” However, he asserted that Guthrie's case has merely become “quiet,” which represents a “very different” scenario.Pack emphasised that investigators are still actively engaged, pursuing leads, and even awaiting an opportunity for someone “to make a mistake” or “a decision to come clean.”“At four months, investigators are doing two things simultaneously. They're going back to the beginning with fresh eyes, reexamining every piece of evidence, every interview, every tip that may have looked insignificant in the first weeks,” he added.Also Read: Nancy Guthrie: Expert expresses ‘disgust’ that FBI hasn’t disclosed ‘enhanced’ suspect pics, ‘the dude looks Spanish’Nancy Guthrie update: Expert says suspects are “watching”Pack also suggested that investigators are meticulously monitoring every detail, as a suspect may “start to crack” and ultimately surrender."They're watching. Watching finances. Watching communications. Watching behavior. Because four months is a long time to keep a secret, and people start to crack," he told Parade. “They make calls they shouldn't make. They spend money they can't explain. They act nervous when there's no reason to be nervous.”Pack further speculated that anyone possessing crucial information regarding Guthrie's purported abduction is likely experiencing sleepless nights at this time."The $1 million reward is still on the table, and that kind of pressure doesn't expire. It compounds," he stated. "Somebody knows something, and the weight of that is getting heavier every single day."Pack expressed to Parade his optimism that Guthrie will be located alive.Nancy Guthrie's children makes heartfelt pleaNancy's three children — Savannah, her brother Camron Guthrie, and sister Annie Guthrie — have made a heartfelt plea to anyone who might be responsible for her disappearance to bring her back.“We will never stop looking for you. We will never be at peace until we find you,” Savannah stated in a Mother's Day post on Instagram.The FBI has announced a reward of $100,000 for any information that could lead to Nancy's return or an arrest in connection with the case. Additionally, Savannah and her family are offering a reward of $1 million.