sanctity of the deceased's wishes

فَمَنۢ بَدَّلَهُۥ بَعْدَ مَا سَمِعَهُۥ فَإِنَّمَآ إِثْمُهُۥ عَلَى ٱلَّذِينَ يُبَدِّلُونَهُۥٓ ۚ إِنَّ ٱللَّهَ سَمِيعٌ عَلِيمٌ

Then whoever alters it [i.e., the bequest] after he has heard it - the sin is only upon those who have altered it. Indeed, Allāh is Hearing and Knowing.