Sayyiduna Ali (may Allah be pleased with him) says: When Sayyiduna al-Hasan (may Allah be pleased with him) was born, I named him Harb. When he (peace and blessings be upon him) came, he said: "Show me my son; what have you named him?" I said: Harb. He (peace and blessings be upon him) said: "No, rather he is Hasan." Then when Sayyiduna al-Husayn (may Allah be pleased with him) was born, I named him Harb. He (peace and blessings be upon him) said: "Rather he is Husayn." When the third son was born, I named him Harb. The Messenger of Allah (peace and blessings be upon him) came to see him and said: "Show me my son; what have you named him?" I said: Harb. He (peace and blessings be upon him) said: "Rather he is Muhsin." Then he said: "I have named them after the names of the children of Harun: Shabbar, Shabbir and Mushabbar."
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الوقف / 11926