Netflix has announced casting updates for its reality series "Selling Sunset" and "Selling the OC." Sandra Vergara, the younger sister of "Modern Family" star Sofía Vergara, will join the cast of "Selling Sunset" for its ninth season. Sandra Vergara, who has approximately two months of real estate experience, is expected to bring new dynamics and drama to the show. Additionally, "Selling the OC" is adding three new female cast members, while some previous cast members such as Alex Jarvis, Alex Rose, Alexandra Harper, Kayla, and Sean will not return for its fourth season. Sandra Vergara's addition to "Selling Sunset" has been highlighted as a notable development in the series' ongoing evolution.