Only wills--and not what people were told, or what they "knew," or even what has been listed in other, non-will documents or correspondence (e.g. emails or letters from the deceased) controls what happens to assets after a person's death, so if there are no wills in effect which state that those were advances, they will not be treated as such, and rather your grandmother's estate will be distributed as per that last or final will.You may be able to invalidate that final will, if by doing so, you will revive or bring back into effect earlier wills that make clear that these were advances on inheritance. To do so, you would need to prove with evidence that one or more of the folllowing was the case:1) Your grandmother was actually mentally incompetent when the will in question in made.2) Your aunts had that will created by fraud--i.e. by somehow tricking your grandmother into signing a will  by lying about its contents.3) The aunts had so much power over your grandmother at the time leading up the will--the most common example is that she was housebound or bedridden, and they were her caregivers, and controlled other people's access to her and her access to the world--that they were able to use that "undue influence" to get her to create a will against her previously expressed interests.4) The aunts threatened your grandmother with violence or other illegal behavior (not just "emotional blackmail") to create and sign that will.5) Your grandmother's signature on that last will was forged.You'll notice that in the above, I keep referring to the paper canceling out prior wills as if it itself were a will. It does not have to a be a full will, BUT it must have been executed (or signed) and witnesssed as per a will. If it was not executed and witnessed the way a will must be in your state, it has no effect: again, only wills--or other documents which meet the  formalities of  being a will--control assets or an estate after death. If the document you refer to was not signed or executed like a will, it has no effect.