Question
We were blessed! But what are they? Parents, red and black, and the other white
with black. Some look like our koi, but most look silvery? It is not a matter of
size. The colored fish are the red, black, white combos and are small. The silvery
ones are just as large, if not larger. What do we have?

Answer
Do you only have koi in the pond or other fish?  If you have goldfish, some of the fry may be goldfish.  If you only have koi, then the silver fry may remain silver or might later get some color.  Koi normally get color at a much younger age than goldfish who can remain gray/brown/blah for years (normally until 1 to 2 inches long).  By the time they are an inch long, most koi have color.  The colors may shift a bit with time though.  

You also can't rule out that the silver fish aren't koi at all but perhaps minnows or shiners or some other fish that ended up in the pond from live plants or visiting animals.  It sounds like you may just have some silver koi though.  

Either way, enjoy them!  My two adult koi have yet to produce young.