Ans.2: Firstly, does your brother pray or not? If he prays the five daily prayers on time, and attends the congregations and the Friday Jumu'ah prayer, then he’s a Muslim. When you mention that he complains not being able to drink alcohol, then this is a sickness in his heart; this is something the Shaytan (Satan) has inflicted him with. This doesn’t prevent you from giving him advice and make it clear to him that alcohol is Haram in Islam and it isn’t permissible to drink it in our religion. You should have good relations with him and connect him with the people of Ahl-al-Sunnah.There is a mosque in America, Masjid as-Sunnah, where the brothers are very good.

As for your feeling that your brother jokes about the religion, then this has to be based on certainty; you have to be certain that he mocks the religion. If he clearly mocks or curses the religion, then you have to tell him that this is not permissible in Islam, and that his actions will be rejected and that causes him to apostate from the religion. It becomes obligatory on him to make taubah (repentance) and that he has to pronounce the Shahadah (testimony of Islam) again. If he isn’t mocking, then he is a Muslim with a sickness in his heart so give him advice and books from the scholars such as Shaykh bin Baaz (rahimahullaah). May Allaah make your family firm upon this Deen and seek help from Allaah ‘Azza wa Jal.