I heard the Messenger of Allah ﷺ say: Allah has appointed for everyone who has a right what is due to him, and no bequest must be made to an heir.  

سَمِعْتُ رَسُولَ اللَّهِ ﷺ يَقُولُ إِنَّ اللَّهَ قَدْ أَعْطَى كُلَّ ذِي حَقٍّ حَقَّهُ فَلاَ وَصِيَّةَ لِوَارِثٍ