Jami` at-Tirmidhi 3775
جامع الترمذي#3775HasanNarrated Ya'la bin Murrah:that the Messenger of Allah (ﷺ) said: "Husain is from me, and I am from Husain. Allah loves whoever loves Husain. Husain is a Sibt among the Asbat." [Asbat, plural of Sibt: A great tribe. Meaning, Al-Husain would have many offspring, such that they would become a great tribe. And this has indeed occurred. See Tuhfat Al-Ahwadhi]
Scholarly Authentication
We show the most cautious grade (weakest-wins) as the overall label. Individual scholars graded it as follows:
Ahmad Muhammad ShakirHasan
Al-AlbaniHasan
Bashar Awad MaaroufHasan
Zubair Ali ZaiHasan
In-book reference: 49:174