Complex sentence: He was the son of George W. Nash, a schoolteacher, and Louise (Walden) Nash (-1892) and had a sister, Carrie Louise (Nash) Thompson (1862-1926), a schoolteacher.
Split into simpler sentences: He was the son of George W. Nash, a schoolteacher and Louise (Walden) Nash (-1892). His sister was Carrie Louise (Nash) Thompson (1862-1926), a schoolteacher.