Is the grandfather's statement to his deceased son's wife, made before the grandfather's death, considered a will or not: "When you return from your trip, I will give her 3000 pounds - God willing -", given that the grandfather died before her return, and the grandmother requested, after the grandfather's death and before the division of the inheritance, that the amount be given to the paternal aunt's wife because the grandfather said so?

The aforementioned صيغة (declaration) is not considered a will, for a will is only established by a صيغة that indicates transfer of ownership after death. Therefore, nothing that the man issued before his death has any legal effect, and the heirs are not obligated to give anything from their money to that woman, except as a voluntary donation. What the man issued was a promise of a gift during his lifetime, and death overtook him before he could execute it. A gift is not completed except by taking possession, and the proof of this is the stance of Abu Bakr with Aisha, may Allah be pleased with them both.