It is narrated from Sayyiduna Abu Rafi' (may Allah be pleased with him) that the Prophet (peace and blessings be upon him) called the adhan in the ears of Sayyiduna al-Hasan and Sayyiduna al-Husayn (may Allah be pleased with them both) when they were born, and he ordered it.
Hadith Referenceالمعجم الكبير للطبراني / باب الحاء / 2566