What is the ruling on offering the sacrifice (uḍḥiyah) using the wealth of a minor or a legally incompetent person (safīh)?
Praise be to Allah, and peace and blessings upon our master, the Messenger of Allah.
It is not permissible for the guardian (walī) of an orphan or a legally incompetent person (safīh) to offer the sacrifice (uḍḥiyah) on behalf of the minor or the safīh using their wealth, because the guardian is charged with exercising caution over their wealth and is prohibited from giving any of it away voluntarily, and the udḥiyah is a voluntary act of charity (tabarru'). The guardian may, however, offer the sacrifice using his own personal wealth. And Allah, the Most High, knows best.
What is the ruling on a mother giving the Zakat of her wealth to her children?
Praise be to Allah, and peace and blessings be upon our Master, the Messenger of Allah.
It is permissible for a mother to give her children from the Zakat if they are among those who are eligible for it—such as being poor (Fuqara), possessing no wealth, and not being sufficiently provided for by the maintenance (Nafaqah) of others. This is based on the statement of the Messenger of Allah ﷺ regarding Zaynab, the wife of 'Abdullah ibn Mas'ud (may Allah be pleased with them both): (Your husband and your children are the most deserving of those upon whom you spend in charity) [Narrated by Al-Bukhari].
It is stated in [Al-Hawi al-Kabir, Vol. 8/P.537]: 'As for the wife, it is permissible for her to pay her Zakat to her husband from all the designated shares... Our evidence is the generality of the saying of Allah the Almighty: "Zakat expenditures are only for the poor and for the needy", and the Hadith of Abu Hurairah that the Prophet ﷺ said to Zaynab, the wife of 'Abdullah ibn Mas'ud: (Your husband and your children are the most deserving of those upon whom you spend), and this is taken in its general sense.' And Allah the Exalted knows best.
What is the ruling on forgoing the sacrifice (uḍḥiyah) for one who is financially able to offer it?
Praise be to Allah, and peace and blessings upon our master, the Messenger of Allah.
It is disliked (makrūh) for one for whom the uḍḥiyah (sacrifice) is recommended (Sunnah) to forgo offering it, on account of the scholarly disagreement regarding whether it is obligatory. And Allah, the Most High, knows best.
Is it permissible to trim the eyebrows if they become excessively long?
Trimming eyebrows is permissible if they become excessively long, yet; it is reprehensible. And Allah Knows Best.