Amr bin Shu'ayb narrates from his father, from his grandfather (may Allah be pleased with him), that the Prophet (peace and blessings be upon him) was asked about the aqiqah, and he (peace and blessings be upon him) said: "Allah, the Lord of Might, dislikes 'al-uquq' (disobedience)." It was as if he (peace and blessings be upon him) disliked the very name aqiqah. And he said: "Whoever has a child born to him and would like to offer a sacrifice on its behalf, then two equal goats for a boy and one for a girl."
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الضحايا / 19274
Zayd bin Aslam narrates from a man of Banu Damrah, from his father, that the Messenger of Allah (peace and blessings be upon him) was asked about the aqiqah, and he (peace and blessings be upon him) said: "I dislike 'al-uquq'." It was as if he (peace and blessings be upon him) disliked the name aqiqah. And he said: "Whoever has a child born to him and wishes to slaughter an animal on behalf of his child, let him do so."
Al-Shaykh (may Allah have mercy on him) said: When this is joined to the first narration, both become strong, and in both of them he made it dependent on one's wish.
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الضحايا / 19275