Stewart Gilligan Griffin is ageless, but his precise age remains a mystery. It's unclear the specific duration of time Stewie became existing. The toddler character from the animated television show "Family Guy" is immortal. His time on Earth is yet to be discovered.
Stewie Griffin, the mischievous baby genius, is keeping his age a secret from the world. Speculation abounds as to the length of time he has existed. Is he over a hundred years old? Or is he a recent arrival? Only Stewie knows! This enchanting character continues to captivate fans with his undisclosed age and perpetually youthful visage.
Griffin family Wikipedia