Unlike his father, John Coe spent much of his childhood growing up in the New World. While Robert moved around Massachusetts and Connecticut, John obtained land in Long Island, where he eventually had over one hundred and fifty acres. However, in 1652, John decided to move to Newtown with his father. Among other improvements to the community, John opened a gristmill near Flushing Creek, which provided grains for the people living in Newtown. John continued to serve the community of Newtown in different capacities, including as a deputy and captain for the English against the Dutch, until his death around 1693.
The gristmill remained in operation long after John Coe's death, standing as a structure until 1875. For the last ten years of its life, the mill served as an inn. After the mill was torn down, the marshes around it were filled in, and in 1930, an expressway was built over the former site of the mill. The expressway was eventually renamed the Long Island Expressway. Today, the site of the mill is completely unrecognizable.