Wasiyyah

Question:

Can parents leave a will (wasiyyah) specifically how much every child will get, but contrary to the text of the Holy Qur’an?

Answer:

Al-Musa Lahu or beneficiary of the will/bequeath cannot be an existing heir. This is based on following hadith:

Narrated Abu Hurairah: Allah”s Prophet (pbuh) said: “Allah has
appointed for everyone who has a right what is due to him, and no
bequest must be made to an heir” [Sunnan Abu Dawood]  Sunnan Abu
Dawood, also similar hadith are reported by Ibn Majah, Ahmed and
others.

The amount that the parents can bequeath is maximum of 1/3 of overall
estate. This means that the parents have  a right to decide to give only 1/3 to
someone other than their existing children.