Simplify the following text for a Grade 7 native English-speaking person.
Original: Simba allows the Outlanders , including Kovu , to return to the Pride Lands , and Kovu is allowed to stand with Kiara at the top of Pride Rock .
Simplified: She plans to raise Kovu to overthrow Simba and become the king of the Pride Lands . This tests not only Kiara and Kovu 's relationship as they mature , but Simba 's relationship with his daughter .