The Messenger of Allah (may Allah's peace and blessings be upon him) slaughtered a ram for Al-Hasan and a ram for Al-Husayn for their ‘Aqīqah
Authentic hadithعن ابن عباس «أن رسول الله صلى الله عليه وسلم عَقَّ عن الحسن والحسين كَبْشًا كَبْشًا».
Ibn ‘Abbās (may Allah be pleased with him) reported: The Messenger of Allah (may Allah's peace and blessings be upon him) slaughtered a ram for Al-Hasan and a ram for Al-Husayn for their ‘Aqīqah.
Explanation
Ibn ‘Abbās (may Allah be pleased with him) says that the Prophet (may Allah's peace and blessings be upon him) slaughtered two rams for Al-Hasan and Al-Husayn when they were born, for each one. This indicates that it is legally permissible to have an ‘Aqeedah for newborns.
Source · Narrated by Abu Daoud
From the Hadith Encyclopedia (hadeethenc.com).