Will Somebody Kindly Explain to Me . . .

. . . how two average mixed-breed horses breed a Clydesdale?   Please see the picture below. I was totally shocked. the parents are in the forefront. Speckles, the sire, bottom left, Moonshine the mare on the right. Bab's Glory, in the background. Take a good hard look at her hooves! That's the mark of a Clydesdale.