I have to agree with stabba the tiny amount of bull blood cant account for much on the wheaten side part of things, ive had wheaten crosses and wheaten/bull/greyhounds for quite a while and have had smooth coats in litters and on the wheaten cross side ive always thought that the smooth coat simply comes from the greyhound, ive found the fawn rough coat throws more in the 5/8 3/8 crosses