Yoreh Deah Siman 16 Seif 8

 

ח צְבִי שֶׁבָּא עַל הָעֵז וְיָלְדָה וְשָׁחַט הָעֵז וּבְנָהּ, לוֹקֶה; אֲבָל הָעֵז שֶׁבָּא עַל הַצְּבִיָּה, אָסוּר לִשְׁחֹט אוֹתָהּ וְאֶת בְּנָהּ, וְאִם שָׁחַט אֵינוֹ לוֹקֶה; הָיְתָה בַּת הַצְּבִיָּה הַזֹּאת נְקֵבָה וְיָלְדָה בֵּן, וְשָׁחַט אֶת הַנְּקֵבָה בַּת הַצְּבִיָּה וְאֶת בְּנָהּ, לוֹקֶה.

 

Seif 8

The offspring of a (male) deer and a (female) goat and one slaughters the goat and its offspring one is liable for lashes (from the Torah); it is forbidden to slaughter mother and son in the case where the offspring comes from a male goat and a female deer, but one does not receive lashes in that case.  If the female offspring of a doe deer with a male goat (i.e. the child of the previous case becomes a mother) one is liable for lashes should he slaughter the female offspring of this deer and its offspring on the same day.