- I think Ben is a fairly insignificant piece of information, mytharc-wise, to go to so much trouble to lie over, don't you?
Anyway - Ben isn't Dean's son. So what? It's not like Dean can't be a father to him. Ben, Lisa and Dean perfectly showcase what SPN highlights so well and what Sam struggled with throughout the entire run thus far: non-traditional families. Bobby, Dean and Sam were a family, and that "family" stretched to include Ellen and Jo as well. So now Dean has a chance at happiness with another family; Lisa and Ben. Doesn't matter that Ben isn't his biological son.