Q: On “I Love Lucy,” did the character Ethel Mertz, played by Vivian Vance, have a middle name? What about her maiden name? How did she and Fred meet? — C.J.J., Binghamton, N.Y.

A: Over the years, Mertz’s middle name has been reported as being Roberta, Louise and Mae. Most character biographies say she was born Ethel Mae Potter in Albuquerque, N.M. Ethel met Fred, played by William Frawley, in vaudeville, where they had a popular act. When vaudeville died out, the couple bought a New York City brownstone and became best friends with their tenants, Lucy and Ricky Ricardo.

Q: Clara Barton, the founder of the Red Cross, was nicknamed “the Angel of the Battlefield.” Is this a nickname from any particular battlefield? When was she born? When was the Red Cross founded? — A.L., Georgetown, Del.