Stewart Gilligan Griffin is timeless, but his exact age is shrouded in secrecy. It's unknown the exact number of years Stewie became living. The baby persona from the animated television show "Family Guy" is immortal. His number of years is yet to be discovered.
Stewie Griffin, the mischievous baby genius, is keeping his age a secret from the world. Speculation is rampant as to how many years he has been alive. Is he ancient beyond measure? Or is he a recent arrival? Only Stewie knows! This mysterious character continues to captivate fans with his hidden age and forever young facade.
Les Griffin Wikipédia