My grandmother died in 1984 & in her will she left 29 acres of mountain ground to the last living survivor of her 11 children. Only 2 children are

If ownership passed from your grandmother's estate to her two children, they became owners outright of the property and can do with the property whatever they want.  Your grandmother's will does not control the disposition of the property once the property is passed to the beneficiaries.  I'm not sure I understand the situation here though.  Your grandmother's will -- if it says last surviving child -- is a really odd disposition. I'm not sure how that would be actually effectuated without holding open your grandmother's estate all these years.  I think there are some facts missing here.  In any event, you can't sell what you don't own so if one child doesn't actually own the property, there's nothing to sell.