They used to sing together. Later one became a singer and the other one, a famous veena player. One of them had a name that is the same as one of the 72 melakarta names!
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Rupavathy (Meḷa 12)
Rupavathi was Veena Dhanammal’s sister, who initially used to perform with her as a duo.
https://www.sahapedia.org/veena-dhanammal-1868%E2%80%931938
https://en.wikipedia.org/wiki/Veenai_Dhanammal