Zhina is a character I asked Kitchiki to help design at one point as a birthday gift for Stalloy and she liked the idea of a Quartzeon, so one of Lazuli's Eevee sisters later evolved into one.
Zhina is quite the adventurer and is always trying to find stronger opponents to battle, so she spends a great deal of time away from home.
Lazuli can readily teleport to be with her big sister at any time and they even go on adventures together, much to Cyra's dismay.
Cyradia is a bit of an overprotective mother, but is particularly so about Zuli and thus tries to keep her on a short leash to protect her. Of course, she was never able to smother the adventurous spirit of her kits and so, begrudgingly, she'll permit her kits to leave.
Cyra also attempts to ensure that Zuli conceals her identity and only permits her to take her natural form when is she alone with either Zhina or Tourmaline, their other Mew sister, because of how strong they are.