A sweet picture book with a different take on metamorphosis and a surprising ending

Two tiny eggs, one in a pond and one on a tree, survive a brutal storm and hatch at the same time. Harold is a tadpole and Grace is a caterpillar. Neither of them can find similar creatures, and they are mocked and ridiculed by those around them until they find each other and become friends. But as they grow, they grow apart. Harold explores further in the pond and leaves Grace behind on her tree. Harold's new friends, the fish, think he's great until he starts growing legs, then they turn on him. Sad and dispirited, Harold returns to find Grace but she is nowhere to be seen; in her place is just a hard little chrysalis. Harold mourns for Grace and keeps vigil over the chrysalis. One morning Harold wakes to something fluttering in the dim light. Hungry, he flicks out his tongue and grabs it, but the fluttering is no meal, it is Grace, hatched at last and now a beautiful butterfly. Back together again they remain true friends and live happily ever after.