The city of Medina witnessed the birth of a blessed boy in the house of Lady Fatimah (A) and Imam Ali (A) on the third of Sha’ban in the year 4 after Hijra.

Imam Al-Hussein (A) was later nicknamed the "Master of Martyrs."  

This newly born baby was the second son of a family whom the Prophet of Islam (S) saluted by the name of "Ahl al-Bayt" (people of the house of the Prophet). They were referred to as Ahl al-Bayt after Prophet Muhammad (S) received the verse of Tat’hir (Purification) (Quran, 33:33). His mother was Lady Fatimah (A), one of the greatest women in history, whose deep knowledge, morality, purity, and other great characteristics are well known, a mother whose rank and status is described by the Holy Quran in a whole chapter. Safia daughter of Abdul Muttalib, Asma daughter of Umais, and Um Salama were present when Imam Hussain (A) was born.

When the Prophet (A) asked Safia (his aunt) to bring him the newborn, she said: "We have not cleaned him yet." When the Prophet heard this, he (S) said: "Do you want to clean him? Surely Allah, the Exalted, has cleaned and purified him"

Asma brought the newborn to the Prophet (A). The infant was wrapped in a piece of cloth. The face of the Messenger of Allah (S) lit up upon seeing his grandson. He took him in his arms. He recited the call to prayer (adan) into his right ear, and read the shorter version (iqama) in his left ear. He, then, placed the baby in his lap and wept.

"May my father and mother be your sacrifice," Asma asked him, "why are you crying?"
"Because of this son," he (S) replied.
"He is a newborn baby," she said.
"O Asma," he (S) said, "After me, the transgressing party will mytyr him. May Allah never grant them my intercession." Then he said: "Asma, do not tell Fatima about this, for she has just given birth to him.

Special Name from God
After Al-Hussein was born, The great angel Gabriel descended to the Prophet (S.) and revealed to him to give the new baby the name, Al-Hussain (A). When Gabriel descended to the Prophet, scores of angels accompanied him to congratulate and console the Prophet for Hussain’s birth and expected martyrdom. Prophet Muhammad (S) named him “Hussain” by the order of Allah (SWT). Hussain is the Arabic equivalent of Shubayr in Hebrew. Shubayr was the name of the second son of Haroun/Aaron, the successor of Musa/Moses (A).
Later this honorable name became synonymous for one who spread knowledge and faith on the earth and his remembrance enveloped all languages of the world and people became devoted to him. So much so that in their view it become a holy slogan for all the high examples and a slogan for every sacrifice that was based on truth and justice.
Prophet Muhammad (S) once informed Imam Ali (A) about the similarity found between Muhammad and Musa, Ali and Haroun, Shubbar and Hassan, Shubayr and Hussain: "O Ali, your status with respect to mine is equivalent to the status of Haroun with respect to Musa, except there will be no prophet after me."
The Holy Prophet (s) emerged from the house in a sorrowful mood because he had received the information from the unseen about the calamities that were to befall the child in the future; such calamities as could shake the complete life of every living person.
The Prophet’s flower (S)
The first voice to reach the ears of Husain (‘a) was that of his grandfather, the Holy Prophet (s) who was the first to have turned towards God and called the people towards Him and his slogan was: “Allah is the Greatest. There is no god except Allah…”
The Holy Prophet (s) inculcated these words into the soul of his grandson; words, which were the essence of faith and reality of Islam and he imbibed these things into the newborn child and taught him about them. They became a part of his elements and basics of his existence. He became absolutely devoted to these concepts in every aspect of his life. Thus he hastened towards the field of Jihad and sacrificed everything so that this formula of faith may be exalted on the earth and powers of righteousness and goodness may become dominant and signs of apostasy of ignorance that were trying to put out the divine light may be subjugated and destroyed.
The Holy Prophet (s) personally took up the rearing of Imam Husain and gave him a lot of attention and mingled his feelings, emotions and aspirations with that of his own. On the basis of what historians state, he used to place his thumb in the mouth of the child. His Eminence took him in his arms and placed his tongue in his mouth so that the exudation of prophethood may be fed to him in the condition that he used to tell him: “Behold O Husain! Behold O Husain! The Almighty Allah has not accepted for you except what He intended, that is Imamate that shall be for you and your descendants.”
Regarding this Sayyid Tabatabai says:
“They (people who martyred him) kept him away from water, thirsty. The one whom his grandfather Mustafa gave him his fingers to suck. Sometimes he gave him his thumb to suck and sometimes his tongue so that his nature may be inculcated into him. The child whom the Prophet himself reared and after his basic goodness there sprouted out from him branches of righteousness (other Imams).”
The Prophet (s) imbibed in the personality of the newborn his personal virtues and excellence so that he may be an exemplar of greatness and this may continue even after he has passed away, and that he may become his successor in spreading his aims and in defending his principles.

Hussain (A) spent his childhood with Lady Fatimah (A), Imam Ali (A), and especially with Prophet Muhammad (S). The love and affection Prophet Muhammad (S) had towards Hussain (A) was so unique that all the companions were aware of it, had frequently seen its manifestation, and had heard of it repeatedly.

Moreover, historians have recorded incidents and narrations in this respect. In one account it has been said that the Prophet’s prostration took longer than usual in his prayer. People came to the Prophet and asked, "Were you receiving a revelation or order from Allah during prostration?" Prophet Muhammad (S) replied, "No, my son Hussain had climbed onto my back; I waited until he wished to come down." This is an example showing how the best creature of Allah (SWT) treated Hussain (A) while he was in the best state of worship. 
The companions had seen Prophet Muhammad (S) repeatedly carrying Hassan and Hussain (A) on his shoulders and play with them. At other times he would kiss Hussain (A) and say, "Hussain is from me, and I am from Hussain. May Allah love him who loves Hussain." In other traditions the Prophet would say, "Hassan and Hussain (A) are my two aromatic flowers from this world."
Nonetheless, most people knew that the Prophet’s love for his two grandchildren, especially for Hussain (A) was not a usual love of a grandfather for his grandchild. According to the Holy Quran, the Prophet’s (S) actions and words are apart from his desires: " Indeed in the Messenger of Allah you have a good example to follow …" (Quran, 33:21).
Prophet Muhammad’s (S) recommendations and affections for Hussain (A) were in fact portraying an important fact. He would repeatedly inform people that salvation and prosperity can only be found through the friendship and love of Imam Hussain (A). Umar Ibn Khattab narrates from Prophet Muhammad (S): "Hassan and Hussain are masters of the youth in heaven. Whosoever loves them has loved me, and whosoever has animosity with them, is my enemy."
In another account the Holy Prophet has also said, "You came to awareness by me; you found the right path and were guided by Ali; you were given blessings through Hassan; but your eternal salvation is with Hussain. Be aware that Hussain is a door from the doors of heaven. Whosoever has animosity towards him can never enter heaven."
The Messenger of God said: “Verily Husayn is a door from the doors of Paradise; God has made even the smell of Paradise unlawful for those who antagonize Husayn.” 
Source: Maqtal Al-Husain By Al-Khawarezmi V1 P14. Bihar Al-Anwar V35 P405 H28
In another narration, this interesting story goes on the blessed birth of Imam Hussein (A): When Imam Husain (A) was born, Allah sent down the angel Gabriel (A) to congratulate the family. On the way down from the heavens angel Gabriel (A) passed a place, on which the angel Fitrus was sent to by Allah because he had been disobedient. Fitrus had also had his wings taken away by Allah.
When Fitrus saw Gabriel (A) he asked him where he was going. Gabriel (A) told him that he was going to congratulate the Holy Prophet (S) and his family on the birth of Imam Husain (A). Fitrus asked if he could also go with him. Gabriel (AS) agreed with the permission of Allah and so carried him down to earth.
When the angels reached the Holy Prophet (SAW) and congratulated him and his family, the Prophet (SAW) told Fitrus to go to Imam Husain (AS). When Fitrus touched Imam Husain’s (AS) cradle his wings were given back to him by Allah and forgiven.
Among the compassions of the Prophet (s) towards his grandsons was his extreme love of the two and his seeking their protection from every evil and calamity by seeking Allah’s refuge for them, and he used to often do this for them.
Ibn Abbas has narrated that: “The Holy Prophet (s) sought protection of Hasan and Husain as follows: ‘I seek by the perfect words of Allah from all devils and poisonous creatures and from all the envious eyes.’ And he used to say: ‘Ibrahim (‘a) used to invoke protection in this way for his sons, Ismail and Ishaq.’

Abdur Rahman bin Auf has reported that: “The Messenger of Allah (s) told me: ‘O Abdur Rahman! Do you not want me to teach you the amulet through which Prophet Ibrahim sought protection of his two sons, Ismail and Ishaq and I do for my two sons, Hasan and Husain…?
Sufficient is Allah as a protector for one who supplicates and there is no place for any archer to shoot an arrow after the command of Allah…’”
This proves the intense love that the Holy Prophet (s) has towards the two Imams and that he feared that evil eyes may strike them; thus he sought their protection through these supplications and amulets.
Holy Quran and Imam Hussain (A)
Imam Hussain (A) was still a child when several verses of the Holy Quran were revealed either about or referring to him. One of those verses is referred to as the verse of Mubahilah (Quran, 3:61). On the day of Mubahilah when a spiritual contest between Prophet Muhammad (S) and the Christians of Najran was set up to invoke the curse of Allah (SWT) on the liars, Hussain (A) and his family were the only ones accompanying the Prophet. Prophet Muhammad (S) had orders from Almighty Allah (SWT) through the verse of Mubahilah to take Hassan and Hussain (A) as his children with him.

Imam Hussain (A) was one of the five people in regards to whom the verse of Tat’hir (Purification) was revealed. He, his father, brother, and mother were under the Prophet’s cloak when Allah (SWT) revealed to His Messenger: "Verily Allah desires to remove all kinds of uncleanness from only you, O Ahl al-Bayt (people of the house), and to definitely purify you." (The Holy Quran, 33:33). 
This verse of the Holy Quran is clear proof of the infallibility of this family and their purification from all sins and mistakes.
In another verse, Allah (SWT) commands all Muslims to love those closely related to Prophet Muhammad (S): "Say: I do not ask of you any reward for it but love for my near relatives?" (Quran, 42:23). When the companions asked Prophet Muhammad (S) who these "near relatives" were, the Prophet (S) replied: "They are Ali, Fatimah and their two children."

Some Traditions of Holy Prophet (S) for Imam al-Husain (AS)

The Messenger of Allah said: "Al-Hasan and al-Husain are the chiefs of the youth of Paradise and Fatimah is the chief of their women."
Also it is narrated that the Messenger of Allah said: "Husain is from me and I am from Husain."

The last part of the above tradition probably means that Imam Husain (A), by sacrificing himself and his family, preserved the religion of Prophet Muhammad (S) from full annihilation.

The Prophet (A) looked toward Ali, Hasan, Husain, and Fatimah (A), and then said: "I am in war with those who will fight against you, and in peace with those who are peaceful to you."

The Messenger of Allah said: "He who loves al-Hasan and al-Husain, has loved me, and he who makes them angry has made me angry."

It is narrated that the Messenger of Allah said: "I named Hasan, Husain and Muhsin, the names of the sons of Aaron (Haroon) who were: Shubbar, Shubair, and Mushbir."

Usamah ibn Zayd narrated: “I went to visit Prophet (S) and he came out with something (I did not know what) under his cloak. When I had finished telling him my purpose to visit him, I asked him what he had under his cloak, and when he opened it I saw al-Hasan and al-Husain under it. He then said, "These are my sons and my daughter’s sons. O Allah, I love them, so I beseech Thee to love them and those who love them.”

Anas ibn Malik Narrated: “When Allah’s Messenger (S) was asked which member of his family was the dearest to him, he replied, Al-Hasan and al-Husain. He used to say to Fatimah, Call my two sons to me and then would sniff and cuddle them.”

The following sources are used to prepare the above article.
2.       The life of Imam Husain (‘a), Baqir Sharif al-Qarashi,  Ansariyan Publications, First Edition 2007