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."
أَنَّهُ كَانَ يَقُولُ ذَكَاةُ مَا فِي بَطْنِ الذَّبِيحَةِ فِي ذَكَاةِ أُمِّهِ إِذَا كَانَ قَدْ تَمَّ خَلْقُهُ وَنَبَتَ شَعَرُهُ
Yahya related to me from Malik from Nafi that Abdullah ibn Umar said, "When a she-camel is slaughtered, what is in its womb is included in the slaughter if it is perfectly formed and its hair has begun to grow. If it comes out of its mother's womb, it is slaughtered so that blood flows from its heart."
أَنَّهُ كَانَ يَقُولُ إِذَا نُحِرَتِ النَّاقَةُ فَذَكَاةُ مَا فِي بَطْنِهَا فِي ذَكَاتِهَا إِذَا كَانَ قَدْ تَمَّ خَلْقُهُ وَنَبَتَ شَعَرُهُ فَإِذَا خَرَجَ مِنْ بَطْنِ أُمِّهِ ذُبِحَ حَتَّى يَخْرُجَ الدَّمُ مِنْ جَوْفِهِ