Back then, it was common for men to have multiple wives. Shahjahan had several wives but he loved Mumtaz the most. He was engaged to Mumtaz to begin with, but he married Khandahari Begum first and then took Mumtaz as his second wife. The whole time, Mumtaz was the object of his affection. It sounds weird and seems wrong now, but back in those times it was nothing unusual. So they were all tharkis back then. 😃
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