Young couple goes on van tour of US, boy comes back with van

Young couple goes on van tour of US, boy comes back with van - no girl

sonicboom said
It's a perfect ending for a family, who didn't look for a woman, when their son comes home without her, in her van.

His parent's (in)actions make a lot more sense if Brian told them that he killed her. If so then they would know that finding her alive was already impossible so then shift to protect their son at all costs mode.