Is Stewie Griffin gay

Answer 1

Quoting Seth MacFarlane:

"We decided it's better to keep it vague, which makes more sense because he's a 1-year-old. Ultimately, Stewie will be gay or a very unhappy repressed heterosexual [which still means he's homosexual]. It also explains why he's so hellbent on killing and taking over the world: He has a lot of aggression, which comes from confusion and uncertainty about his orientation."

And he told The Advocate: "He originally began as this diabolical villain, but then we delved into the idea of his confused sexuality. We all feel that Stewie is almost certainly gay, and he's in the process of figuring it out for himself. We haven't ever really locked into it because we get a lot of good jokes from both sides, but we treat him oftentimes as if we were writing a gay character."

Essentially he either "gay" or "straight" depending on the scene. If the scene requires him to like guys than he likes guys if he needs to be interested in girls than he is.

Answer 2

No. He was killed in the S12 episode Life of Brian but Stewie altered the time line and saved him 2 episodes later in Christmas Guy,

Answer 3

During a holographic simulation in the episode, "Lois Kills Stewie", Stewie did die.

Answer 4

He was hit by a speeding car although Stewie altered the timeline and saved Brian's life.