Being a Sagittarius born on December, your personality is defined by an assertive, honest and restless nature. You value honesty in all aspects of life, which may explain why those closest to you would describe you as blunt or frank. You openness is especially witnessed when there is something you want, as you will express and pursue your interests with great assertiveness. Your assertive nature may also explain for your restlessness. You often have so many varied interests that it is hard for you to remain satisfied in routine. Happy Bday!