Reference
Moonshot's Answer
Franz Kneisel urged Lillian Fuchs to switch from violin to viola in 1926 so that she could play in a quartet led by his daughter, Marianne Kneisel. This decision was made to fill a need for a violist in the ensemble, and Kneisel recognized Fuchs's potential to excel on the viola. Lillian Fuchs eventually became a prominent violist, and this switch significantly influenced her career. Images of Lillian Fuchs can be found in various sources, including here and here.
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