Simba and Nala’s daughter in The Lion King II: Simba’s Pride is Kiara.
Kiara is introduced as the central character of the 1998 direct-to-video sequel. She is Simba’s first cub, the princess of the Pride Lands, and the heir expected to become its future queen. Her adventurous personality frequently worries her protective father, especially when she crosses paths with Kovu, a lion raised by Scar’s former followers.
Kiara’s story drives the sequel’s main conflict. She falls in love with Kovu despite the long-standing hostility between their families, helping Simba and the Outsiders move toward reconciliation. She is voiced by Michelle Horn as a cub and Neve Campbell as a young adult.
Vitani is Kovu’s sister, Zira is Kovu’s mother, and Sarabi is Simba’s mother, so none of those names fits the question. Kiara later appears in The Lion Guard and has a younger brother, Kion.