Zhian'tara

The zhian'tara is a Trill ceremony, where a joined Trill meets their symbiont's previous hosts.

A Guardian transfers the personalities and memories of a previous host to the current host's volunteers through telepathy. The former host's personality comes to the fore and interacts with the current host, allowing the current host to ask questions and learn more about the previous hosts. The rite gives the current host an insight on how previous hosts influence the symbiont and their joined behaviors. The volunteers can release the consciousness back to the symbiont.

The Symbiosis Commission requires all hosts to undergo the ceremony. 

In 2373, during Tawana Jonar's zhian'tara, two unintended side-effects emerged when Yh'ahni was Ulitania Jonar; it unlocked Yh'ahni's early memories, including her parents frantic battle and escape with unknown aliens, and triggered primal urges in Yh'ahni. (: "Finding The Edges Of Who She Is")