The number 4 is considered unlucky in Chinese culture; it sounds similar to the word for "death" in both Mandarin and Cantonese.
The temple was inspired by the Bok Kai Temple, a historical landmark in Marysville, California that was built by the local Chinese community in 1880. A special thanks is made in the credits.
The family's nickname for Meilin, "mei-mei," is Mandarin for "little sister."
Ming's character was originally written to have been incredibly happy that Mei turned into a red panda because it was a good luck charm for the temple, and she would have planned to monetize Mei's red panda form for profit. This direction for Ming was scrapped due to Domee Shi feeling it made her too much of a "one-note villain."
The red pandas guarding Meilin's family temple are based on Buddhist Nio guardians. One has its mouth open, the other closed, symbolizing the birth and death of all things.