Stewie is eternally young, but his exact age is shrouded in secrecy. It's unknown the specific duration of time Stewie became living. The toddler character from the animated television show "Family Guy" is forever young. His time on Earth is still determined.
Stewart Gilligan Griffin, the mischievous baby genius, is keeping his age a secret from the world. Speculation abounds as to how many years he has been alive. Is he over a hundred years old? Or is he a recent arrival? Only Stewie knows! This enigmatic character continues to captivate fans with his hidden age and perpetually youthful visage.

Saison 4 des Griffin Wikipédia