It is narrated from Sayyiduna Abu Zayd al-Ansari (may Allah be pleased with him) that one day the Prophet (peace and blessings be upon him) passed among the houses of the Ansar and noticed the smell (of meat being cooked). He said: "Who has slaughtered before we slaughtered our sacrifice?" A man came out and said: It is I, O Messenger of Allah. Today is a day on which a shortage of food is felt (so I slaughtered early). He (peace and blessings be upon him) said: "Then do (the sacrifice) again." He said: By Allah, besides whom there is no true deity, I have nothing except a young sheep less than a year old, or a lamb. He (peace and blessings be upon him) said: "Then slaughter that, and a young animal will not suffice (as a sacrifice) for anyone after you."
Hadith Referenceالمعجم الكبير للطبراني / باب العين / 14123