Hadith #2834 (Sunan Abi Dawud)
Book: Sacrifice (Kitab Al-Dahaya)
Narrator(s): Abu Yazid al-Makki أبو يزيد المكي, Masdad bin Masrhad مسدد بن مسرهد بن مسربل, Saba' bin Thabit, Sufyan bin Sa‘id Ath-Thawri سفيان الثوري, Ubaidullah bin Abi Yazid عبيد الله بن أبي يزيد المكي
Grade: Sahih

I heard the Messenger of Allah (ﷺ) say: Two resembling sheep are to be sacrificed for a boy and one for a girl.
AbuDawud said: I heard Ahmad (ibn Hanbal) say: The Arabic word mukafi’atani means equal (in age) or resembling each other.

Source: https://parallelquran.com/hadith/sunan-abi-dawud-2834/