Will was the third boy to live on The Rocks in the Stoneship Age. He was found by Emmit, who gave Will his name. He, Emmit, and Branch became fast friends, swimming and fishing in the ocean around The Rocks, and living in a small cave in the largest rock. When a young girl and a male adult appeared near The Rocks, Will was the first to spot them.
By the time the Stranger arrived on Myst and began to uncover the history of what had happened there, Branch and the other people who lived on The Rocks were gone. It is unclear whether they fled when Sirrus and Achenar began to exploit their father's Ages, or were subjected to the brothers' destructive behavior.