臣 chén, originally meant “male slave”, is a character with very little “siblings” in Chinese characters. Totally, there are only seven characters composed of 臣:
卧/臥 wò; 临/臨 lín; 藏 cáng,zàng; 臧 zāng; 臤 qiān; 臦 guàng; 臩 guǎng. Only these three are commonly used: 卧/臥 wò; 临/臨 lín; 藏 cáng, zàng.
文言版《説文解字》：臣，牽也。事君也。象屈服之形。凡臣之屬皆从臣。
白话版《说文解字》：臣，被牵拉。表示侍奉君王。字形像一个人屈服之形。所有与臣相关的字，都采用“臣”作边旁。