- Dec 16 Ethan Dolan, American Vine and YouTube star with twin brother Grayson, born in New Jersey
- Dec 16 Grayson Dolan, American Vine and YouTube star with twin brother Ethan, born in New Jersey
- Dec 17 Holly Humberstone, English singer-songwriter ("The Walls Are Way Too Thin"), born in Grantham, England
About December 1999
How Old? 23 years old
Generation: Generation Z
Leap Year: No
Chinese Zodiac: Rabbit
Star Signs: Sagittarius (Nov 22 - Dec 21), Capricorn (Dec 22 - Jan 19)