Fanny Mendelssohn Hensel (November 14, 1805 - May 14, 1847) was Felix Mendelssohn's older sister. The two siblings were very close and studied music together as children. She was also a child prodigy; like Felix, she played the piano and composed music. At 13 years old, she performed all 24 preludes from Bach's "The Well-Tempered Clavier" by memory for her father's birthday.

Unfortunately, during her lifetime, many people did not believe that women should be composers or professional musicians. Her father felt that it should only be a hobby for her. She did perform at the regular concerts in the Mendelssohn home and often played her own compositions. Because these concerts were attended by important people, she did gain some recognition as a musician.

Fanny continued to compose music throughout her life and wrote over 460 works. Most of her music was not published during her lifetime, although Felix arranged for a few of her works to be published under his name.
When she married a painter named Wilhelm Hensel, he supported her composing and sometimes drew illustrations for some of her pieces.

Felix was very close to his sister and greatly respected her musical talents. He often consulted her opinions on his music before showing new pieces to anyone else. Fanny died of a stroke when she was only 42. Felix, devastated and in poor health from overwork and exhaustion, died of the same thing only six months later.