Complex sentence: The real John'Grizzly' Adams did not have a middle name, however, his mother's maiden surname was Capen, and he did have a younger brother who was actually named James Capen Adams.
Split into simpler sentences: The real John'Grizzly' Adams did not have a middle name. However, his mother's maiden surname was Capen, and he did have a younger brother who was actually named James Capen Adams.