Dean didn't waste time when it happened, because Sammy was in pain And it was all his fault.
He'd tried so hard to stop it. - so hard to keep his brother safe.
But this was a Winchester thing, so there was no getting around it.
Bobby saw it in all the Winchesters of course.
The drift.
Each would go from duty… to determination… to doubt. And finally the guilt that lead to self destruction.
So Dean's desperate call came as no surprise to Bobby.
Nor to Castiel.
Because (although they didn't know it) two angels always guarded the Winchesters.