James Cooper and his sister, Cassandra, were introduced in Season 7, Episode 21, when traveling companions, the Coopers, got in a wagon accident. The children were riding with Charles and the parents were in their own wagon when, on a steep downhill road, the horses got spooked and the wagon brake broke off, leading to a wagon roll-over off the roadside, resulting in the deaths of the Cooper parents.
Unable to find a home for the Cooper children, Charles and Caroline take them in, eventually adopting them.