Is it permissible for one to shake hands with his uncle`s daughter?
No, it isn`t because he is a non-Mahram (Marriageable) to her.
What should a person who doubted having missed a pillar of prayer do?
All praise be to Allah, The Lord of The Worlds. The prayer of one who doubts having missed one of its pillars is valid, and nothing is due on him/her since having a doubt after offering the act of worship doesn`t undermine its validity. And Allah Knows Best.
What is the ruling on someone who doesn`t perform prayer?
All perfect praise be to Allah,The Lord of The Worlds Not performing prayer is a major sin, and one who doesn`t pray out of laziness is considered an oft-sinner ;whereas, the one who denies that it is mandatory is considered a disbeliever. And Allah Knows Best.
Does undergoing surgery under anesthesia break the fast?
Anesthesia itself does not break the fast because anesthetic gases have no physical substance (jirm), and subcutaneous anesthesia injections do not reach the body cavity (jauf). However, this is on condition that the person is conscious at some point during the fasting hours:
● If they were awake at the beginning of the day, their fast remains valid.
● If they wake up even for a moment before sunset, their fast is also valid.
However, if the surgery involves the entry of foreign substances into the body cavity, their fast is invalidated, and they must make up for that day later.