What is Zara brand sister?

Excuse me, could you please clarify what you mean by "Zara brand sister"? Zara, as I understand, is a well-known international clothing and accessories retailer. However, I'm not familiar with the term "Zara brand sister" being used in the context of the fashion industry or business. Are you perhaps referring to another brand that is affiliated with or similar to Zara in some way? If so, could you please provide more context or specific details about the brand you're inquiring about?