Is it Halaal for me to take money from my Christian grandmother in Christmas time as a gift? Especially when I am locked up and I need the money desperately.
Secondly I would like to ask, if I am not a Muslim, can I fast the month of Ramadhaan for my best friend who just passed away recently last month and he is a Muslim.

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. We ask Allaah to exalt his mention as well as that of his family and all his companions.

There is no harm on you in taking the money that your grandmother gives you as a gift at the occasion of Christmas. There are evidences from the Sunnah that it is permissible in general to accept the gift of a non-Muslim. It is confirmed in Al-Bukhari and Muslim narrated that Ukaydir Doomah, had offered a gift to the Prophet and he accepted it. He also accepted the gift given to him by Muqawqis who was the king of Egypt. He gave the Prophet two slave girls and a mule. [Ibn Khuzaymah and others] The ruling about accepting a gift from non-Muslims on the day of their celebration, is like accepting the same at other times: which is permissible, and the day of celebration does not affect the ruling about accepting gifts from them. Accepting a gift (on such occasion) is not helping in falsehood.

Shaykh Al-Islaam Ibn Taymiyyah said: 'As regards accepting a gift on the day of their celebration, we have previously stated that 'Ali Ibn Abu Taalib was given a gift on the day of celebration of the Persians and he accepted it.' Ibn Abu Shaybah reported that 'A woman said to Aa'ishah that she used to have a Magi wet nurse who used to offer her a gift on the day of their festival. So 'Aa'ishah said: "Do not eat the meat they sacrificed on this day, but do eat the fruits." Then the Shaykh further said: 'So all this is an evidence that the day of feast does not affect the prohibition of accepting their gifts, as its ruling applies to the day of their festival and other days.'

Therefore, there is no harm in accepting the gift given to you by your grandmother, on the condition that this gift should not be a reason for being amiable to her as Allaah says (interpretation of meaning): {You (O Muhammad ) will not find any people who believe in Allaah and the Last Day, making friendship with those who oppose Allaah and His Messenger (Muhammad), even though they were their fathers, or their sons, or their brothers, or their kindred (people).}[58:22]. We advise the questioner to call his grandmother to Islaam, as she has a priority to be called to Islaam since she is your close relative. As regards the fasting of the month of Ramadan by a non-Muslim, it is not valid whether he fasts for himself or on behalf of another person, because Allaah does not accept any act from a non-Muslim before he embraces Islaam. Allaah says (interpretation of meaning): {And We will approach [i.e. regard] what they have done of deeds and make them as dust dispersed.}[25:23]. Allaah also says (interpretation of meaning): {The example of those who disbelieve in their Lord is [that] their deeds are like ashes which the wind blows forcefully on a stormy day; they are unable [to keep] from what they earned a [single] thing. That is what extreme error is.}[14:18].

Finally, we draw the attention of the questioner that if he is a Muslim, then it is not permissible for him to say "If I were a non-Muslim", but rather he should say for instance: "Is it permissible for a non-Muslim to fast on behalf of his friend..?" and so forth.

Allaah knows best.