Complex sentence: Usman has a beautiful relationship with his niece, Aaliya, and so, when a situation arises where Zain alone can save Aaliya from disgrace, he insists on their marriage, believing that Aaliya would be the making of his son.
Split into simpler sentences: Usman has a beautiful relationship with his niece, Aaliya. When a situation arises where Zain alone can save Aaliya from disgrace, he insists on their marriage, believing that Aaliya would be the making of his son.