Though Lani in The White Lotus seemed like she could be a key character in season 1, she ended up making an abrupt exit. The White Lotus episode 1 introduced plenty of characters including both staff and guests, though one character, Lani, surprisingly never returned. HBO's The White Lotus follows the complex lives of the wealthy guests and employees at the exclusive White Lotus resort in Hawaii over the course of a week. As The White Lotus season 1 progresses, the dark nature of the privileged guests’ lives, amorality and exploitation of employees, and imperialist impact on the native Hawaiian culture are slowly revealed.

https://screenrant.com/white-lotus-lani-pregnancy-birth-not-return-reason/