(1805–47), German pianist and composer, born in Hamburg; eldest sister of composer Felix Mendelssohn; considered as talented musically as her brother and a better pianist; was his chief musical adviser until he left home; organized local concerts in Berlin, occasionally appearing as a pianist; wrote some 500 compositions, including about 120 piano pieces, many art songs, and chamber music, cantatas, and oratorios; six songs published under Felix's name; the few works published under her own name include collections of short piano pieces, art songs, and a piano trio; remainder unpublished; son wrote biography of Mendelssohn family based partly on her diaries and letters.