I don't know what the average age is for people to have an existential crisis, but mine came at an early age, about five or six, maybe four...
I was sitting on the stairs, staring at the wall, holding my head with my palms wrapped around my chin when my mom came to ask me what was wrong.
I'd been sitting there pondering the reason of life and, not having developed much in the way of abstract thought, I said to my mom, "I don't think I have a reason for living..."
I remember her consoling me, "Oh Joseph, we all have a reason for being alive. You'll find yours."
She was probably completely caught off guard, and not entirely sure what more to say, but then a white bird flew into the window, and before it even had a chance to start falling, we saw the front half of one of our cats come leaping up and grabbing it with both paws.
I flew out the door to the porch and grabbed the cat, which immediately let go of the bird. I ended up with a small puncture on my forearm that I'd thought was from the bird pecking me, but looking back now, I imagine it was probably from the cat. I still have a small dent in my skin now.
I went back into the house with a huge grin, happy with myself for rescuing the bird. My mother told me the bird was an angel who came to let me know I did have a reason for being here. Even from a Buddhist perspective, with the Bodhisattva Avalokiteśvara, or the Great Vows, the idea doesn't seem so far-fetched.