Maliks Muwatta Book 024, Hadith Number 009.

Section : Slaughtering What is in the Womb of a Slaughtered Animal.

Yahya related to me from Malik from Yazid ibn Abdullah ibn Qusayt al-Laythi that Said ibn al-Musayyab said, "The slaughter of what is in the womb is included in the slaughter of the mother if it is perfectly formed and its hair has begun to grow."