Kevin wasn't always a Winchester.
When his parents were killed by a
demon, the church sought Sam, in
hopes that he could lure the boy out of
his shell and back into the normal
Unfortunately Kevin didn't want to
return to the normal world, he wanted
to kill the thing that kill his parents, and
no one was going to stop him.
Sam adopted the boy and has been
helping him adjust, as well as training
him to be a hunter. He would rather
see him out there doing it right than on
his own, getting himself killed.
Over time Kevin began to fit in with
the Winchester clan, which was
made up oddly enough of more
non Winchesters than actual
He loves Sam, and has recently
started to call him Dad instead of
He is gifted with the hunt, but
seems to have an almost comical
ineptitude with cars... and girls.