It is Wajib upon the parents to bear the expenses of the children right from the time of their birth till they become independent, and in case of a daughter, till she gets married.
Arranging the Marriage
One of the most important duties of the father is to arrange for the marriage of the son when he attains maturity. In case of the daughter too the father must strive to find a good match for her. The parents cannot restrain their daughter from matrimony. The Holy Quran states clearly:
"...then do not prevent them from marrying their husbands when they agree among themselves in a lawful manner."
(Surah Baqarah 2:232)
Religious Education and Training
Another important duty for the parents is to give a good education to their children. The parents must strive to instruct the children with regard to the fundamentals of Islamic faith. The seriousness and significance of observing the laws of Shariat should be inculcated in the children, and no leniency must be shown if the religious laws are not strictly followed. However, the aspect of Amr bil Maroof and Nahy Anil Munkar must be kept in mind. The details regarding the same shall be explained in the chapter of Amr bil Maroof (enjoining good) and Nahy Anil Munkar (forbidding evil).
Various traditions stress upon the duty of the parents to shower their love and affection upon the children. A few of these are quoted below.
Love and Affection For the Children
The Holy Prophet (s.a.w.s.) said:
"Be affectionate to your children and have mercy upon them. When you promise them something, fulfill your promise because the children repose hope only in the parents. When a promise is not fulfilled, it causes dissatisfaction and strains relationships. Certainly Allah is most wrathful when the women and children are disheartened."
Kissing the Children
The Holy Prophet (s.a.w.s.) has told that when a person kisses his child, a good deed is recorded in his Nama-e-Aamal (Scroll of deeds).
Daughters Are More Deserving of Kindness
The parents have been ordered to be more kind towards the daughters. It is mustahab that when a father brings something for the children he must first offer it to the daughter; especially the one who is named Fatima.
If the children oppose the parents, they must never be abused or reviled. The curses of the parents cause an increase in the misery of the children.
Spiritual Fathers Are More Qualified For Kindness
Whatever has been mentioned till now concerns the biological parents; however the spiritual fathers or the guides of humanity are Hazrat Muhammad (s.a.w.s.) and his Purified Ahlul Bayt (a.s.). All of us are spiritually related to them. In every circumstance their followers can be enriched by virtues and get protection from calamities. The Holy Prophet (s.a.w.s.) has informed, "I and Ali (both) are the fathers of this Ummat." The spiritual fathers are superior to the biological parents in a manner that the soul is superior to the physical body. Similarly the punishment of the 'Aaq' of the spiritual fathers is much more severe than that of the 'Aaq' of ordinary parents.
High Rewards and More Punishment
The rewards for kindness to the spiritual father is a thousand times more than kindness to the real parents. In the same way the 'Aaq' of a spiritual father is far more severely punishable, i.e., Heaven is prohibited for the person who disobeys the spiritual father, and none of his deeds are accepted even if he prays in the nights and fasts during the day. The punishment for those who do not acknowledge the Wilayat of Ahlul Bayt (a.s.) is more severe because the Ahlul Bayt (a.s.) are the real spiritual fathers. It would be wrong to consider all the Quranic verses and traditions in connection with Uqooq-e-Waledain to be restricted to biological parents. The Holy Quran and hadith are unanimous in declaring that the commands for Uqooq-e-Waledain apply equally and more stringently to the spiritual as well as biological parents. The ultimate argument in this connection is the Quranic verse wherein Allah has ordered obedience towards the parents along with His own worship.
"Be grateful to Me and both your parents."
(Surah Luqman 31:14)
"And your Lord has commanded that you shall not serve (any) but Him, and goodness to your parents."
(Surah Bani Israel 17:23)
A similar reference to the Holy Prophet (s.a.w.s.) and the Ahlul Bayt (a.s.) is to be found in the chapter of Sileh Rahem. Two traditions are reported from Imam Ja'far as-Sadiq (a.s.)
The first tradition is when Umroo bin Yazid enquired about the meaning of the following Ayat of Surah Raad:
"And those who join that which Allah has bidden to be joined and have awe of their Lord and fear the evil reckoning."
(Surah Raad 13:21)
The next tradition is concerned with the tafsir of the same 'Ayat'. It says that the above Ayat has been revealed about the Sileh Rahem to Muhammad (s.a.w.s.) and the Ahlul Bayt (a.s.), the close relatives of the Momin being included in it. The tradition further says,
"And do not be of those who restrict the Ayat to some particular personalities. But whenever you hear of a verse regarding a kind of people you must consider it to be applicable to the other people of the same kind."
source : GREATER SINS by Ayatullah-ul-Uzma Sayed Abdul Husain Dastghaib Shirazi (r.a.)