Is it permissible for them to use their father’s money when he does not pray?

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:
My father, May Allah guide him, does not pray. He does not pray unless he is in a public place or at work, so he does not become embarrassed if people notice that he does not pray. But he does not consider prayers with care. An imam and a congregation from a masjid have advised him to pray, he prayed for a few weeks then stopped. He used to pray Friday prayer before, and now he stopped even praying the jumu’ah prayer.
  My question is: Is his money that he spends on us halal or haram? Does the hadeeth of the prophet, peace be upon him that says: “There is no flesh that is nourished by haram things, but the Fire will be more entitled to it.” Apply to us, his children, or not?.
(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:
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Answer:
Praise be to Allaah.

Firstly: 

Not praying is a major sin and cause of doom; in fact it is kufr according to the more correct of the two scholarly opinions, as has been explained in the answer to question no. 5208 and 2182. 

The kufr of the one who does not pray leads to numerous rulings in life and after death. Meat slaughtered by him is not halaal, it is not valid for him to be a wali (guardian) or witness in case of marriage, and if he dies he is not to be washed or the prayer offered for him, and he cannot be buried with the Muslims. 

You should carry on calling him, advising him and reminding him, in the hope that he may repent and come back to Islam. See the answer to question no. 47425. 

Secondly: 

The money that he spends on you is not regarded as haraam or impure, so long as he earns it in a permissible manner, such as a job or trade and the like. What is meant by the hadeeth, “Every body that is nourished on haraam, the Fire is more befitting for it” [narrated by al-Tabaraani and classed as saheeh by al-Albaani in Saheeh al-Jaami’ (4519)] is wealth that is taken in haraam ways such as stealing, deceit and so on. 

We ask Allaah to guide you and give you strength, and to guide your father and enable him to repent. 

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

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