Original: Jehan's original name was Sonya Rizvi but she changed her last name to Jehan in honor of her grandmother, Noor Jehan, a legendary singer and actress in British India and Pakistan.
Simplified: Sonya's original name was Sonya Rizvi but was re-christened with the last name Jehan to honor her grandmother, Noor Jehan, who is a legendary singer and Lollywood actress.