What is the constellation od someone being born on 1999?

The constellation for someone born in 1999 depends on their specific birth date, as the zodiac signs change roughly every month. For example, someone born between January 20 and February 18 would be an Aquarius, while a person born between March 21 and April 19 would be an Aries. To determine the exact zodiac sign, you would need the precise birth date.