When my sister and I were little, we had an almost daily ritual with my father: drawing stories.

He would sit us on his lap and get out his clipboard, a piece of paper and his black click pen. He’d divide the paper into four parts, and draw as he told a story. Sometimes he drew old favorites and we knew what would be in each of the four drawings. Sometimes he let us decide what he should say and draw. But most of the time, we had no idea what would come next.

And that was really fun.

He came by it honestly. My grandfather was an incurable storyteller, an Irishman full of blarney who never felt particularly constrained by the truth. Once when my cousins were visiting, he told them that marshmallows grew on the bushes outside. “Marshmallows don’t grow on bushes, Grandpa!” they exclaimed — and pointed out that there were no marshmallows on any bushes anywhere. “Sometimes they come out overnight,” he told them. When my cousins fell asleep, he went out and bought marshmallows and stuck them on the bushes. “See?” he told my cousins. “I told you.” He said it with such authority and calm, they believed him.

My father was the same way. Anything was possible, even the most unlikely things — which, with a twinkle in his eye, he could often make us believe. But it wasn’t just about marshmallows on bushes or gentle giants curled up in closets or talking animals; it was about imagination, pure and simple. It was about the idea that there was so much that could be seen, thought and created — and that this could be sheer fun.

It added a whole dimension to my childhood, one that I took for granted. My father made it magical — and as he drew and painted, wrote stories or played the piano, so did we. Everything we saw, every person we met, everything we did was, or could be, more intricate and interesting. We loved books and art and music not just because they were wonderful, but because they gave us ideas, building blocks to create new stories, paintings and songs.

(He also taught us how to tell some pretty convincing stories, which came in very handy when we didn’t finish our homework or when we didn’t want our mother to know what we’d been up to.)

Sometimes my father made fun of me with the stories, like the ones he drew when I was applying to college. I was reasonably freaked out about it, and the stories helped. Like the ones he drew when I was little, about the brave little girl who conquered whatever came along (insert fear of week: the dark, dogs, getting lost), the stories about the silly teenager with the permed hair helped put things in perspective — and helped me see that ultimately, how I see my fears, and the world, is up to me.

That lesson has meant everything.

My father died suddenly in 2005. I didn’t get to say goodbye, I didn’t get to tell him how much I loved him — or how grateful I am to him.

I so wish I could say: Daddy, thank you so much for the stories.

Claire McCarthy is a pediatrician at Boston Children’s Hospital. She blogs at the Huffington Post, where this article originally appeared, and at Boston.com as MD Mama.