'Aishah (RAA) narrated, "Allah's Messenger (ﷺ) commanded them to slaughter two sheep equal (in age) for a boy and one for a girl at their birth.' Related by At-Tirmidhi and graded it as Sahih. (IT)
English reference (IT): Book 12, Hadith 1398 (IT)
Arabic reference (IT): Book 12, Hadith 1357 (IT)