Mishkat al-Masabih 30 Fine Qualities كتاب المناقب 161

وَعَنْ أَنَسٍ قَالَ: لَمْ يَكُنْ أَحَدٌ أَشْبَهَ بِالنَّبِيِّ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ مِنَ الْحَسَنِ بن عليّ وَقَالَ فِي الْحسن أَيْضًا: كَانَ أَشْبَهَهُمْ بِرَسُولِ اللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ. رَوَاهُ الْبُخَارِيُّ

Anas said no one more closely resembled the Prophet than al-Hasan b. `Ali, and he said of al-Husain also that he was the one who bore the closest resemblance to God’s messenger. Bukhari transmitted it.