Assalaamu ‘Alaykum; Please calculate the inheritance according to the following information
۞-Does the deceased have male relatives who are entitled to inherit:
(A son) Number 1
۞-Does the deceased have female relatives who are entitled to inherit :
(A daughter) Number 1
(A wife) Number 1
۞- The will which the deceased left behind and that is related to his inheritance is
:
the quranic distribution with respect to inheritance should be followed

All perfect praise be to Allaah, The Lord of the Worlds. I testify that there is none worthy of worship except Allaah, and that Muhammad is His slave and Messenger.

If the heirs are only those mentioned in the question, then the wife gets one-eighth of the inheritance because of the existence of the children of the deceased; Allaah Says (what means): {But if you leave a child, then for them is an eighth of what you leave.}[Quran 4:12] The remainder should be divided among the son and the daughter, the male twice the share of the female; Allaah Says (what means): {Allaah instructs you concerning your children [i.e. their portions of inheritance]: for the male, what is equal to the share of two females.}[Quran 4:11]

Indeed, the deceased did well by making a will so that his inheritance would be divided according to the Sharee’ah, and this is an act of advising others to truth. However, whether or not he made a will to this effect, inheritance should be divided according to the Book of Allaah.

Finally, it should be noted that the matter of inheritance is very complex an issue, so a mere Fatwa which is an answer issued according to the question is not enough. Rather, the matter should be taken to an Islamic court to look into the case or to what could serve instead like the Islamic centers in non-Muslim countries so that they would be able to determine the inheritance the rights related to the inheritance and the heirs and knowing the rights that are related to the inheritance like a will or debts and so forth.

Allaah Knows best.