SAN DIEGO -- It's been two years since a Fallbrook family of four went missing, and one of their relatives is still looking for clues in their disappearance.
In February 2010, Joseph McStay, his wife, Summer, and two sons suddenly vanished from their home in Fallbrook, leaving virtually no clues as to what happened to them.
In an exclusive interview with NBC 7, Joseph’s brother, Mike McStay, said he has been desperately searching from day one and that it has become an obsession.
Sitting at the computer for hours on end, Mike McStay checks the website he created for his brother Joseph and his family, which features pictures of Joseph's wife and two small sons, Gianni and Joseph Jr.
People from nearly everywhere have been sending Mike McStay information on possible sightings.
"You think you're on a trail and the door just gets shut in your face," McStay said.
The frustration over the case also weighs heavily on homicide detectives.
Detective Sergeant Dave Martinez says all investigators found at the McStays home in Fallbrook were eggs on the counter and the family dogs, who were left unfed.
"There was no evidence of a struggle and there was no evidence of a forced entry," Martinez said.
Investigators did get one clue from Joseph's cellphone. At about 8:30, an hour after the family left the home, a call went through a cell tower in the Bonsall area. According the show E investigates, the call appears to have been made near the old Bonsall Bridge.
"I've always wanted to search that area," said McStay, "now there were a lot of rains that year, wash outs and stuff, and I'm not sure what we'll find, but to me personally that's something that is plausible."
However, investigators say it appears the McStays went willingly to Mexico.
In a grainy video taken at the border, a family who resembles the McStays can be seen walking across the border.
"It's compelling. It tells you that it could be them," McStay said. But he has his doubts.
Mctsay says the man in the video appears to be carrying an infant on his chest possibly in a baby byorn. Furthermore, he said his brother has a teenage son from a previous marriage and would never willingly cut off their relationship.
"They're not cruel people they wouldn't put their families through this," McStay said. "I know them. I don't think they would behave that way."
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