Is it permissible for a wife to boycott (not to attend to his different needs) her husband?
It isn`t permissible for the woman to boycott her husband unless he is the reason behind that, and it is recommended that both spouses seek the advice of righteous people to make reconciliation.
What is the ruling on deliberately breaking the fast while being capable of fasting?
Whoever intentionally breaks their fast in Ramadan without a valid excuse has committed a major sin and bears great guilt. They must repent, seek forgiveness, refrain from eating and drinking for the rest of the day, and make up for that day after Ramadan.
They have lost an immense reward, which cannot be compensated even by fasting an entire lifetime as a voluntary act, because an obligatory fast cannot be equaled by voluntary fasting.
If the fast was broken through sexual intercourse, the person must:
● Make up for the missed fast (qada), and
● Perform kaffarah by fasting two consecutive months.
● If they are unable to do so, they must feed sixty needy people.
Is it permissible for a guardian (Big brother) to unlawfully stop his sister from getting married?
If the guardian denies her right in getting married for an unlawful reason, she should go to court in order to settle that matter, and the guardian is considered sinful in this case.
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.