I did more research. And figured that Stacy had the physical build of her Holstein mother, but looked and acted more like a British White, and since Rone also resembles a British White bull, I figured that his mother should be a British White cow.
Leanna is stubborn, but on the docile side, she won't act out at her humans, but doesn't always like to do what she's told (ie: won't move when pushed, try to walk away from being milked, will swat with tail, but she won't kick, trample, or anything aggressive) she was mostly a pet cow among the livestock on the ranch, but had calved/been milked before. When Clayton is brought in, the shy, docile bull grew a fondness for the pretty white cow with the grayish freckles.
Leanna had a rough time calving Rone, due to having some Holstein genes and being bigger than expected. The humans quickly realized by Rone's star birthmark who the father was, and expected to have a docile bull for future breeding.
Joke was on them. Rone inherited Oberon's temper and overall ornery demeanor, but luckily, he did not inherit Oberon's black heart, as his seemingly uncontrollable behavior tamed upon meeting his lovely mate, Lady.