SHAFAQNA- Hussain (A.S) spent his childhood with Lady Fatimah (S.A), Imam Ali (A.S), and especially with Prophet Muhammad (A.S). The love and affection Prophet Muhammad (P.B.U.H&H.P) had towards Hussain (A.S) 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 (A.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 (S.W.T) treated Hussain (A.S) while he was in the best state of worship.
The companions had seen Prophet Muhammad (A.S) repeatedly put Hassan and Hussain (A.S) on his shoulders and play with them. At other times he would kiss Hussain (A.S) 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.S) 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.S) was not a usual love of a grandfather for his grandchild. According to the Holy Quran, the Prophet’s (A.S) actions and words are apart from his desires: “Indeed in the Messenger of Allah you have a good example to follow …” (The Holy Quran, 33:21) On the other hand, although Prophet Muhammad (P.B.U.H&H.P) had other adopted daughters and a son, the specific affection and recommendations were only shown towards Hassan and Hussain (A.S).
Prophet Muhammad’s (P.B.U.H&H.P) recommendations and affections for Hussain (A.S) 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.S). Umar Ibn Khattab narrates from Prophet Muhammad (A.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.”
Taken from: Islamic Shia information site