Raccoon used to love (and demand!) stories in the car. He was probably 2-4 years old or so, and found car rides difficult. I would tell him Peter, John, and Pepe stories. Peter was a little boy, John was his dragon friend, and Pepe was their skeleton friend from a local museum who was very particular about his red paint, which he thought looked like blood. They usually flew off on John to look for treasure, or occasionally to rescue someone.
Kitty's stories have been at bedtime, and much more varied in scope and characters, although her favorites are Tea (Tae-ya) stories, especially Why and his stabby stabs. I found countless notes on my phone with little scenarios jotted down, like guinea pig with wings flies to new town, princess decides not to marry and gets superpowers instead, etc. Since I tell Kitty her stories as we fall asleep at night, I realized that not even I remembered the story the next day. It would all be there in my mind with perfect clarity, but by the next evening it would be gone. I started jotted down little snippets so I could tell her the next installment the following evening, although now not even the snippets make sense to me anymore, having forgotten the stories they belonged to.
Telling stories to kids is a good test, because something has to happen very regularly for them to stay interested. It has been a blessing to share my made-up stories with my babies.