Xiongdi 兄弟宮Zi Wei's twelve palacesZi Wei Dou Shu 紫微斗數

兄弟宮 sits immediately after 命宮, and the order itself says something: the closest people aren't parents or partner but the ones standing on your level. The tradition has it cover siblings, peers, colleagues and business partners, because structurally those are one category — no rank, only alongside.

So what it actually reports is how you handle equality: whether you can share, whether you can compete without falling out, whether you can move something with nobody outranking anybody. That's a lifelong difficulty for many people, because hierarchies come with rules and parallel relationships don't.

It's also the palace read for partnerships, for a practical reason: a partnership is peers by definition, and the trouble in peer relationships was never ability. It's division.