Arunita sang it Kishore Kumar special and PD in Rekha Ji's dream sequenceð
But both were solos. I don't remember any duet performance.
There were I think 3 times PD had to sing the song Arunita had already sung - and how can you better perfection?
But the Kalank song - I think both sang differently. PD did it first and it waa full of anguish. ArK did it later and it was very mellow. Both did a spectacular job I felt.
Sorry to digress...
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