A hatchery that sells the Blue Orpingtons, which shall remain nameless, apparently crossed in Blue Rocks at one point to offset the closely related birds; At least that's what I heard, so take this with a grain of salt. So later on, on occasion, yellowish legs were popping up in their Blue and Splash Orpington lines. In fact, one of Skye's splash cockerel babies started out with yellowish legs, only one I ever heard of out of my girl. They actually changed color later and became white, which was the wildest thing I'd ever seen. Anyway, maybe that's partly the reason for the yellowish-looking legs. Just food for thought.