Complex sentence: He married the Hon. Elizabeth Massy, widow of John Arthur of Seafield, and daughter of Hugh Massy, 1st Baron Massy and his first wife Mary Dawson, and had a son, Sir Richard Eyre Cox, 4th Baronet.
Split into simpler sentences: He married the Hon. Elizabeth Massy, widow of John Arthur of Seafield, and daughter of Hugh Massy, 1st Baron Massy and his first wife Mary Dawson. They had a son, Sir Richard Eyre Cox, 4th Baronet.