In 1853 Mary's father died, leaving her a large inheritance. The Morgans bought a brownstone in a wealthy suburb of Rochester. In that year their son, Lemuel, was born, who "turned out to be mentally handicapped."  Lewis' rising fame brought him public attention. Lemuel's condition (on no specific evidence) was universally attributed to the first-cousin marriage. The Morgans had to endure perpetual criticism, which they accepted as true, Lewis going to far as, in Ancient Society , to take a stand against cousin marriage.  The Morgan marriage remained a close and affectionate one. 
For an excellent source on English composition, check out this classic book by William Strunk, Jr. on the Elements of Style. Contents include: Elementary Rules of Usage, Elementary Principles of Composition, Words & Expressions Commonly Misused, An Approach to Style with a List of Reminders: Place yourself in the background, Revise and rewrite, Avoid fancy words, Be clear, Do not inject opinion, Do not take shortcuts at the cost of clarity, … and much more. Details of The Elements of Style by William Strunk, Jr. partially available online at . Note: William Strunk, Jr. (1869–1946). The Elements of Style was first published in 1918.