"He'll be back soon," he says, dropping heavily onto the couch. "Said he just wanted to drive around and clear his head." Which he wouldn't need to do if they just told Bobby the truth. But if it was lie forever or lose him by telling the truth, Sam would choose the lie every single time. It was easier to keep the secret when they weren't staying with Bobby anyway. Soon enough they'd be on the road, and the stress would be gone.