Is the son of the sister by breastfeeding considered a mahram in Islam, and is it permissible for a woman to go for Hajj with him?
Everything that is prohibited by lineage is also prohibited by breastfeeding. The son of the sister by breastfeeding is considered a mahram, just like the son of the sister by blood, and it is permissible for him to be her mahram for Hajj and Umrah. And Allah Knows Best.
Is it permissible for a woman to perform the obligatory prayer immediately after the adhan and before the Iqamah is performed in the mosque?
Praise be to Allah, and peace and blessings be upon our Master, the Messenger of Allah.
Yes, it is permissible for a woman to perform the obligatory (Fard) prayer immediately after the Adhan (call to prayer) and before the Iqamah (call to commence prayer) is performed in the mosque. And Allah the Exalted knows best.
What is the ruling on performing dry ablution (tayammum) on a wall or stone?
One of the conditions for tayammum is that it be with pure, clean dust (soil). It is not valid to perform tayammum by striking stones, a wall, sand that has no dust (i.e., that does not produce dust), pebbles alone, or clay, as these are not from the earth or its same category. And Allah the Almighty knows best.
What is the ruling of Islamic Law on making up missed voluntary prayers?
All praise is due to Allah, and peace and blessings be upon our master the Messenger of Allah ﷺ.
It is recommended for a Muslim to make up any missed voluntary prayers — whether the regular Sunnah prayers (rawātib), the witr prayer, or his personal devotional routine (wird). As for voluntary prayers that are tied to a specific cause or occasion — such as the eclipse prayers (kusūf and khusūf) — these are not made up once their time has passed.
Shaykh al-Islām Imām al-Nawawī, may Allah have mercy upon him, stated: "The correct view in our school is that making up the regular voluntary prayers is recommended." [Al-Majmūʿ, Vol. 4/P.43] And Allah the Almighty knows best.