No will for an heir

Dear Brothers & Sisters,
As-Salaamu-Alaikum wa Rahmatullahi wa Barakatuh. (May Allah's Peace, Mercy and Blessings be upon all of you)
One of our brothers/sisters has asked this question:
If a person states in his will that one-third of his wealth is to be given to the poor, is it permissible for his heirs to take some of this bequest if they are poor?
(There may be some grammatical and spelling errors in the above statement. The forum does not change anything from questions, comments and statements received from our readers for circulation in confidentiality.)
Check below answers in case you are looking for other related questions:
She has a company with her husband; if he dies, will his second wife and her children inherit it?
Inheritance of properties

Answer:
Praise be to Allaah.

Yes, that is permissible. Shaykh al-Islam [Ibn Taymiyah] (may Allaah have mercy on him) said: “It is not permissible to make a will leaving something to an heir without the consent of the other heirs. Heirs may be included in the will in general terms without mentioning them by name.” (al-Ikhtiyaaraat, p. 190). 

What this means is that if a will is in general terms, i.e., it does not mention people by name, such as one that mentions categories, such as the poor, or students, or mujaahideen, etc., it is permissible for those who fall into those categories to take something from this bequest even if they are also heirs. But if the will mentions people by name, such as bequeathing wealth to relatives, the heirs cannot be included in this bequest. 

And Allaah knows best.

Whatever written of Truth and benefit is only due to Allah's Assistance and Guidance, and whatever of error is of me. Allah Alone Knows Best and He is the Only Source of Strength.
Your brother and well wisher in Islam

Related Answers:
Do the grandchildren get anything from the estate due to the law of binding wills (wasiyah waajibah)?
The father and mother have died, and before the estate was divided, one of the sons died, and left behind a wife and daughters
They inherited wealth from their father and invested it in some business; how should they pay zakaah?
She has a company with her husband; if he dies, will his second wife and her children inherit it?
Inheritance of properties

Recommended answers for you:
The punishment for homosexuality
Is it possible to talk to the jinn and use them?
Virtue and times of regular Sunnah prayers (Sunnah mu’akkadah)
Visiting the sick – some etiquettes
Coping with wet dreams