What are the conditions that must be met for the 'aqīqah to be valid?
All praise is due to Allah, and may peace and blessings be upon our Master, the Messenger of Allah.
The 'aqīqah is like the recommended uḍḥiyyah in terms of the type of animal, its age, and its required characteristics — since it is a recommended slaughter and therefore resembles the uḍḥiyyah in its rulings.
It is agreed upon without any difference of opinion that the 'aqīqah is not valid with any animal other than livestock (al-na'am — camels, cattle, and sheep). Likewise, an animal with a disqualifying defect — such as obvious illness, lameness, or blindness in one eye — does not suffice, as has previously been explained in the rulings of the uḍḥiyyah. And Allah Almighty knows best.
Is it permissible for a wife to give her money to her family as a charity, or a gift without asking her husband, or seeking his consent?
The wife has the right to give her money as a charity, or a gift to her family, or to other people after consulting her husband out of respect, and this is the meaning of treating on footing of kindness and equity. Therefore, if he wanted to stop her from helping her family, then there is no harm in not telling him.
Is it incumbent on a father to cover the marriage costs of his son if the latter couldn`t afford them?
The son should seek the help of his relatives in order to convince his father to do the aforesaid, and the father should make sure that his son doesn`t commit fornication through helping him to get married, and Allah will reward him for doing so.
Which holds greater virtue: The Udhiyah (Sacrificial Offering) or giving its value in Charity (Sadaqah)?
In the Name of Allah, and may peace and blessings be upon our Master, the Messenger of Allah.
Offering an Udhiyah (sacrificial offering) holds greater virtue than donating its monetary value to the poor and needy. This is because the sacrifice is a prominent, manifest ritual among the sacred symbols of Islam. Allah Almighty says: "That [is so]. And whoever honors the symbols of Allah - indeed, it is from the piety of hearts." (Al-Hajj: 32)
Furthermore, there are numerous authentic and explicit Hadiths highlighting its immense reward. The Prophet (peace and blessings be upon him) consistently offered this sacrifice, as did the Righteous Caliphs after him. And Allah the Almighty Knows Best.