Sheriff Joseph Lombardo, who has called Danley a "person of interest" in the attack, said that "we anticipate some information from her shortly", and said he is "absolutely" confident authorities will find out what set off Paddock.
Law enforcement is hoping she sheds light on who Paddock was and why he did what he did.
The official said no evidence has been found that Paddock ever came to Chicago that weekend.
"He manipulated her to be completely as far away from this and safe when he did this", Eric Paddock told reporters.
Mr Bustos said he immediately contacted his younger sister when he saw the news that Paddock had opened fire on music fans from the 32nd floor of the Mandalay Bay Resort and Casino. She traveled to Hong Kong on September 22, then returned to Manila on September 25 before leaving Manila for the U.S. The 62-year-old was initially described as a "traveling companion" of Paddock's and a person of interest, but it's unclear what line of questioning authorities intend to pursue with her.
She also stated that she believed the trip to the Philippines and the money for the house was a way for him to break up with her. One radios in: "I'm inside the Mandalay Bay on the 31st floor, I can hear automatic fire coming from one floor ahead. one floor above us".
An unidentified acquaintance of Danley who was contacted by the Reno Gazette-Journal said: "She had nothing to do with this psycho".
Agents from the Federal Bureau of Investigation continue to process evidence at the scene of the mass shooting.
Authorities have yet to release a motive in the attack but were still sorting through Paddock's hotel room and his multiple homes, where they found an arsenal of more than 40 firearms. Danley traveled with an Australian passport.
"No one can put the puzzles together, no one except Marilou", one of the sister's told Channel 7. The 62-year-old was allegedly sent to stay with her family by the shooter shortly before the massacre.
The shooter wired $100,000 to an account in the Philippines before he carried out the massacre. "Marilou Danley is my sister".
This could be the same $100,000 which a United States official said Paddock transferred to the Philippines in the days before the shooting.