Rasool Allah SAW used to love his grandson and many times smelled him as some one smells the flowers. Many times when Rasool salal laho aliehi wasalam was praying he used to climb his back and Prophet salal laho aliehi wasalam elongated his prostration so that this great child is not disturbed.
Sahabas rizwanullahee aliehim ajma een also used to love him from the core of their hearts because he and his bother Syedna Hassan had a physical and facial resemblance with Rasool salal laho aliehi wasalam and when they saw them memories of prophet salal laho aliehi wasalam were refreshed in their minds.
Syedna Hussain radi Allahu anhu was a pious person who spent his life in worshiping of Allah swt and left this world as shaheed.
His love is the part of our faith because he is a lovely member of the family of prophet salal laho aliehi wasalam. His name is evergreen till the day of judgement and Muslim families name their off springs after his name due to their love for Rasool salal laho aliehi wasalam and his family. May Allah be pleased with him and include us among his lovers for the sake of Allah swt.