I believe it was disha who made the suggestion of memory serves. But yeah she would never want Pragya to meet her own daughter she’s always hated Pragya because unlike abhi, she saw straight through Aliyas lying deceitful nature
Disha suggested it then aliya agreed and then aliya convinced abhi for it so she was equally involved in the decision of pragya leaving rhea in abhi's care. It's not like it happened against aliya and abhi's will.
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