I think that Nala and Vitani are half-sisters. Now, before you disagree, hear my theory out.
We all know Nala's basic story. Born under Mufasa's reign, she is close to the age of Simba. Her mother is Sarafina and her father is unknown, most likely a rogue lion. She has blue-green eyes similar to her mothers, and is light in color, as well as a small backwards chin-tuft. She is the mate of Simba and mother of Kiara (and Kovu, anyone?).
As for Vitani... well, we know very little about her, but here are some basics: Most likely born under Scar's reign, she is slightly older than Kovu, estimated to be about 1-2 months his senior. Her lineage is unknown, leaving it open for speculation. She has blue-lightpurple eyes, and a backwards chin-tuft similar to Nala's, not to mention her signature head-tuft, which is unusual for a lioness. If she had a mate, he is unknown.
Now, for my theory.
Scar, being king, could take whatever mate he wished, and after siring Nuka, realized Zira could not provide him a suitable heir. He mated with Sarafina, Nala's mother, in hopes of a son more suited to the throne than his first. Sarafina bore him Vitani, though she could not be a Scar's heir because she was female. Not wanting any connection with Scar, Sarafina refused to care for her new daughter, leaving Zira to take Vitani in while she was still very young. Vitani grew up with Zira as her mother, but knowing of her true parents. Nala was also alerted to her new half-sister, leaving an untrustworthy relationship between the two as Vitani was taken with Zira after the Outsiders were banished from the Pridelands.
So do you see? It all kind of fits. Vitani and Nala even share some physical similarities, given to them by their mother, such as blue eyes, the backwards chin-tuft, and their light fur color. Vitani looks more like an Outsider because, of course, Scar was an Outsider, while Nala's father most likely resembled more a Pridelander.
Their age differs because, as said above, Nala was born under Mufasa's reign while Vitani was most likely born under Scar's, seeing as in my theory, Scar is Vitani's father. This puts at least five years between them, seeing as Scar ruled during all the years Simba was chillin' with Timon and Pumbaa.
Also, this also explains the obvious rivalry between Vitani and Nala in TLK 2: Simba's Pride.
So, what do you think?
