(NewsNation Now) — As families gathered to celebrate Thanksgiving this week, one father, David Robinson, spent the holiday handing out flyers promoting the search for his missing son.

David’s son, Daniel Robinson, 24, vanished June 23 while working in a remote area of Buckeye, Arizona.

Police have said they have no evidence of foul play or violent criminal activity. However, Robinson’s blue Jeep was found by a rancher one month after he was reported missing. His keys, wallet and cellphone were in the vehicle but there was no sign of him.

Some who have examined the case, including the family’s private investigator, Jeff McGrath, aren’t so sure there was no foul play. McGrath doesn’t believe Daniel Robinson was in his car when it flipped over, and recently pointed out to NewNation that “the vehicle had 11 additional miles on it from when the airbags deployed. It had 46 additional ignition cycles on it after the airbags deployed.” McGrath also said there was paint on the vehicle that couldn’t be attributed to the place it was found.

David Robinson told Marni Hughes Friday on “NewsNation Prime” that a recent conversation with a federal law enforcement official may help clarify the timeline of his son’s disappearance. The official, Robinson said, told him that he had seen his son on the morning of June 23 and Daniel seemed healthy and clearheaded.

It’s another detail that the father hopes will help bring him closer to his son.

“We have to go based on everything we do know,” said the elder Robinson. “That’s what’s keeping me there in the desert. But when I do hear of sightings or any kind of leads, we do follow those. Because we don’t know what happened at that scene where my son’s vehicle was found. So everything is open. We have to look in every direction and we’re following those (leads).”

It has been a long uphill climb to find the facts of the case.

“It’s hard, every day is like the first,” David Robinson said. “You know, just try to make sure I keep my son’s name out there. And I’m really grateful for the volunteers who tirelessly come out there every week. That’s very encouraging to me. It keeps me going. The strength of my family, the strength of God.”

In the area of the search, human remains have been found, he said, though not those of his son. The presentation of that new information to Buckeye Police Chief Larry Hall, Robinson said, may lead to new developments.

“Chief Hall, he did agree with the suspicious nature, and … he told me he was going to bring in the FBI to take a look at my son’s case,” Robinson said. “So I’m really relieved to hear that.”

Anyone with information about the case is urged to click on pleasehelpfinddaniel.com or call (803) 200-7994.