Brian disappeared from his parents house in North Port, Fl., back in September 2021, shortly after Gabby was reported missing following the pair's cross-country road trip, from which the late 22-year-old never returned home.
Just days later, her remains were found near a campground at Grand Teton National Park in Wyoming, with Brian being named as the main person of interest in what was ruled a homicide.
In a new report from The Sun, a source close to the family — who wished to remain anonymous — said Brian "was contemplating everything," before he disappeared, including the impact the case would have on his family members.
After authorities were unable to track down Brian for an entire month, his body was eventually recovered in the Carlton Reserve in Florida, where he died by suicide from a gunshot wound to the head.
While many assumed Brian was evading authorities because of his involvement in Gabby's death, an insider has revealed he was trying to keep his mother from getting arrested.
"He promised his parents he would wait until they issue an arrest warrant and then turn himself in and fight the case. But that whole day was awful," the source stated, referring to September 13, 2021, when Brian claimed he was going for a hike in the reserve only to never return home again.
The source claimed that Brian's parents, Chris and Roberta Laundrie were talking to their lawyer, Steven Bertolino, before their son fled, when "Steven was on speaker phone, and Brian heard him say police might arrest his mom."
"That's when he left," the source explained. "His dad tried to tell him to stay since he was leaving upset, but Brian said he needed to get fresh air and clear his head, which wasn't unusual for him."
"It was a bad day, and his mind was made up," dished the source, who also gave a current update on the grieving parents.
"The bottom line though is that his mom blames herself," the insider added. "And his dad is falling apart. It kills me because it's not his fault. He didn't cause this and he doesn't deserve this. He was always a good dad. I get such an awful knot in my stomach knowing he's suffering so much."
As OK! reported, Brian's parents have now been sued by Gabby's parents — Joseph Petito and Nichole Schmidt — who claim the Laundrie's knew more than they were letting on about their daughter's disappearance after she was reported missing.
"While Joseph Petito and Nichole Schmidt were desperately searching for information concerning their daughter, Christopher Laundrie and Roberta Laundrie were keeping the whereabouts of Brian Laundrie secret, and it is believed were making arrangements for him to leave the country," the lawsuit filed earlier this month read.