For the herd of elephants at the San Diego Zoo Safari Park, family isn’t just the main thing. It’s everything.

Two male African elephants born at the San Diego Zoo Safari Park—Emanti and eMacembe LaLu Hlata, better known as “Mac”—are now residing at the Caldwell Zoo in Tyler, Texas.

Two lactating African elephants—Umngani (pronounced OOM-gah-nee), who gave birth to a healthy female calf, Mkhaya or “Kaia”, on Sept. 26, 2018; and Ndulamitsi, known as Ndula, who gave birth to a healthy male calf, Umzuli-Zuli or “Zuli,” on Aug. 12, 2018—are participating in a nutritional study, allowing researchers to study the content of their milk.