Praise be to Allah.
Firstly:
In the answer to question no. 763 we mentioned the deeds that may benefit the deceased. These deeds may be done in the hope that Allah, may He be exalted, will accept them, and on the basis of thinking positively of Him, may He be glorified. But as for stating definitively that these deeds will be accepted, no one can be certain of that.
Secondly:
If your brother (may Allah have mercy on him) did not fast during Ramadan because of an excuse such as sickness, travelling or being unable to fast, and that excuse remained valid until Allah took him in death and he was not able to make them up, then he does not owe anything and his heirs do not have to make up these days when he did not fast.
However, if he was sick with an illness for which there was no hope of recovery, then in that case he came under the same heading as an old man who is not able to fast, so poor people should be fed on his behalf, because this is what was required of him when he was alive, to feed the poor instead of fasting.
But if he did not fast for some legitimate reason and he died without having made up what he could have made up when he had the opportunity to do so, then his heirs may fast on his behalf. But if he did not fast on some days in Ramadan out of carelessness and heedlessness, and he had no excuse, then it is not valid to make up the fasts on his behalf.
Please see the answers to questions no. 81030 and 174581
Thirdly:
The fact that his sister sees him in her dreams living in a verdant garden is a good thing, in sha Allah, and there is the hope that he is blessed by that and that Allah has bestowed upon him the favour of a good status before Him. But we cannot be certain about any such matter. Dream interpretation is a vast topic and it is very difficult to be certain of anything in that regard. But we should focus on the blessing of Allah and the hope of His kindness and grace.
Muslim (479) narrated that Ibn ‘Abbaas said: The Messenger of Allah (blessings and peace of Allah be upon him) drew back the curtain and the people were lined up in rows behind Abu Bakr. He said: “O people, there is nothing left of the glad tidings of Prophethood except a good dream that a Muslim sees or that is seen for him.
In the answer to question no. 731 we stated that the belief of Ahl as-Sunnah wa’l-Jamaa‘ah is that we do not testify that a particular person will go to Paradise or Hell, except in cases where the shar‘i texts affirm that.
With regard to some people sensing that their time of death is near, this cannot be denied in general terms, especially when there are signs that point to that, although no one knows exactly when his time will be up or where he will die. Such matters are of no great significance and have nothing to do with a person’s virtue or status. Allah knows best what happens of such things. However we may be definite about what we have said above, that no one knows when his life will end or where he will die. Allah, may He be exalted, says (interpretation of the meaning):
“Verily, Allah! With Him (Alone) is the knowledge of the Hour, He sends down the rain, and knows that which is in the wombs. No person knows what he will earn tomorrow, and no person knows in what land he will die. Verily, Allah is All-Knower, All-Aware (of things)”
[Luqmaan 31:34].
And Allah knows best.
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