Caroline was the daughter of Johann Ignaz Willmann (1739–1815), a musician, playing flute, violin and cello; and his second wife Marianne de Tribolet, an opera singer.
[1] An early appearance in a concert in Kassel with her mother in February 1811 was reviewed in the Allgemeine musikalische Zeitung: "As a pianist, she has several times received well-earned applause.
Alexander Wheelock Thayer wrote: "Her voice—she was but eighteen years old—was not powerful, but very pure and sweet, except in the middle tones, and of remarkable extent in the upper register."
"[3] In 1816 to 1818 she appeared at the Theater an der Wien in Vienna; roles included the Queen of the Night and Elvira in Mozart's operas The Magic Flute and Don Giovanni.
She appeared in 1819 in Munich and Stuttgart, 1820 in Dresden, 1823 in Kassel, and 1825 in Berlin; Thayer commented "with varied success".