The Messenger of Allah ﷺ said to al-Hasan ibn Ali. This son of mine is a Sayyid (chief), and I hope Allah may reconcile two parties of my community by means of him. Hammad's version has: And perhaps Allah may reconcile two large parties of Muslims by means of him. (Using translation from Abū Dāʾūd 4662)
قَالَ رَسُولُ اللَّهِ ﷺ لِلْحَسَنِ بْنِ عَلِيٍّ «إِنَّ ابْنِي هَذَا سَيِّدٌ وَلَعَلَّ اللَّهَ أَنْ يُصْلِحَ بِهِ بَيْنَ فِئَتَيْنِ مِنَ الْمُسْلِمِينَ عَظِيمَتَيْنِ»