Stewie is ageless, but his specific age is shrouded in secrecy. It's unknown how old Stewie has been existing. The infant persona from the animated television show "Family Guy" is forever young. His time on Earth is yet to be determined.
Stewie Griffin, the clever little troublemaker, is hiding his true age from the world. Speculation is rampant as to how many years he has been alive. Is he over a hundred years old? Or is he a recent arrival? The answer is known only to Stewie! This mysterious character continues to captivate fans with his undisclosed age and perpetually youthful visage.

Family Guy Quel âge a Stewie Tout sur le Adoxa