Be certain to read the small print on HD fruit trees. Labeling a white sapote tree "Vernon" when it is in fact a seedling will not get you the desired results. HD sells "Cate" macadamia trees from Laverne that are labelled "Cate", but are seedlings of Cate and that fact is written in small print on the label. You won't get "Cate" characteristics from a seedling if only one parent is Cate.
Plant a white sapote seed and graft it over to the true variety you want from a reliable source. White sapotes are easy to graft and you can have a tree with many varieties grafted on it.
I should have my head examined. I knew Laverne sold "Manilla" mango seedlings, it didn't even dawn on me to think the rest of their "cultivars" are seedlings too. I bought 2 WS from Mimosa last year, but they were from Laverne too. I just bought a Vernon from HD on Friday. I'm going to have to see if I can find a graft point and see if the label has the fine print you talk about. I ordered some Big Jim loquats too. These seedlings as well?
Oh well, live and learn. I'll be returning the HD one if it's a seedling.
Edit: Just called Laverne. The lady said all their trees are grafted, including the WS and loquats, except for a few exceptions. She says all their mangos are grafted except for the manilla. I could have sworn the graft line was easily visible but you had me doubting myself.