Would it possibly say on a registration paper whether a horse is a carrier or not?
Beside the fact that frame can show in a tobiano, that would mean a parent would have to have been overo or somewhere down the lineage there would have to be a frame carrier. I just looked on Lena's pedigree, as far down as I can go there is all tobiano's, not an overo in sight, there is absolutely no way she could be an OLW carrier.
Though, the stallion is overo. Not sure on his status. The foal she had with him, the one in the picture, had one blue eye.