As time passed and the monkey sat on the floor collecting dust he began to be able to move his limbs. Over time he became able to crawl, walk, and eventually leap and perform impressive acrobatic feats. The monkey’s button eyes, which had been old and faded now gleamed gold.
His golden eyes shined so bright that even the God of the Universe noticed them and he sent two of his servants to investigate. They reported back to their king that it was just a harmless sock monkey having fun by himself. He presented no danger at this time.
The monkey continued to play by himself until one day he came across a pack of real monkeys. The monkeys were hesitant to hang out with the sock monkey, but once they saw that he could do anything that they could they became friends.
It was a particularly hot summer and the sock monkey and his friends were all cooling off by a secluded pond. One of the monkeys felt adventurous and did a cannonball into the pool. Another monkey had an idea and said, “Whoever can make the biggest splash will be king of us all.”
The sock monkeys turn came, and he mustered all his strength. He prayed to the gods that gave him life. When he jumped, right before he hit the water his sock body became as hard as stone. He produced a splash so giant that all the other monkeys were completely soaked. And from that time on he was known as the King of the Apes.

Author's Note:
I took the story of how Sun Wu Kung got his name and made it more absurd. I changed a monkey made of stone into a sock monkey. In the original story Sun Wu Kung jumped off a cliff into a waterfall and finds a heavenly cave. In my version he just makes a big splash.
Bibliography:
The Chinese Fairy Book, ed. by R. Wilhelm and translated by Frederick H. Martens (1921).