Haley Collins is the sister of Tommy Collins, who went missing while on a camping trip.
When Sam and Dean Winchester are in the area investigating earlier disappearances, Wilkinson mistakes them for friends of Haley's and, on a hunch, they go to visit her. She shows them the last video her brother Tommy sent her via cellphone before he disappeared. She also informs them that she and her younger brother, Ben, have hired a guide and are heading into the hills to find Tommy the next morning.
Sam and Dean arrive in Blackwater the next morning just as Haley, Ben, and their guide, Roy, are setting out for Tommy's campsite. When the group reaches the campsite, they find ripped tents and damaged equipment. Later, after Roy is killed and Dean and Sam explain that it was a Wendigo that took Tommy, Haley and Dean are themselves taken by the creature. Sam and Ben follow a trail of peanut M&M's that Dean leaves behind and they eventually find Dean, Haley, and Tommy hanging from the ceiling of an abandoned mine. They cut them loose and escape, and Dean kills the Wendigo. Haley talks with Dean, and thanks the Winchesters before leaving with Tommy and Ben in the ambulance.