Am I supposed to believe that Cole was younger than Dean?

One of the things that pulled me out of this storyline (aside from the whole entire storyline itself) is that Cole saw Dean off his daddy when he was a kid, but every time Cole is on-screen, I'm like damn, they look the same age. Matter of fact Cole looks a little older. Casting made no sense to me whatsoever. Also really wish they scrapped this story altogether. And dude can't act