Complex sentence: Justin, Richard, Kendeall, David, Grace, Kyle, Peyton, Jennie, and Matthew--and 16 great-grandchildren, some of whom walked with her for portions of her cross-country trek.
Split into simpler sentences: Justin, Richard, Kendeall, David, Grace, Kyle, Peyton, Jennie, and Matthew--and 16 great-grandchildren. Some of these people walked with her for portions of her cross-country trek.