The FBI confirmed that the human remains found at a Florida reserve are those of Brian Laundrie, but questions still remain for his parents.

The search for Laundrie has led to questions about his parents' involvement especially after a breakthrough in the case was made Wednesday when they joined law enforcement in the search.

Investigators found the human remains at the Carlton Reserve alongside Laundrie’s backpack and notebook.

Former NYPD detective Ralph Cilento says the discovery of the notebook could be key in finding out why Laundrie’s fiancé Gabby Petito was killed and what happened to Laundrie himself.

“That lends itself to suicide,” Cilento says. “Maybe he wanted to write his last thoughts. Maybe he wanted to write down a confession and then his suicide note.”

Attention is on Laundrie’s parents following Petito’s homicide and their son’s disappearance.

Cilento, of the John Jay College of Criminal Justice, believes that Chris and Roberta Laundrie have been deceitful since the beginning and know a lot more than they were saying.

For weeks, Brian Laundrie’s parents have been largely silent as law enforcement scoured the 24,000-acre nature reserve for their fugitive son.

The discovery of the remains Wednesday came when Chris and Roberta Laundrie told law enforcement to search an area of the reserve that had been underwater.

“It seems clear that the odds of them looking in an area and then the parents just happen to be in that area, those odds of coincidence drop quickly for me,” Cilento says.

Cilento says there has been a lot of suspicious conduct by the Laundrie family including dropping off and picking up the cars at the reserve and remains being found in the area parents told law enforcement to look in after the water receded. He also says the family misdirected police which reserve to look at and Brian Laundrie's sister lied about not speaking to him.

“Just too many coincidences here to not believe on some investigative level that the Laundrie family was complicit in his escape,” Cilento says.

If the parents are proven to be complicit in Brian Laundrie’s escape, Cilento says they could be charged with harboring a known felon or lying to investigators.

He says the possibility of those charges may have led to the Laundries to cooperate with investigators in Wednesday’s search.