Les Soeurs Siamoises.

First daughters of Rotten Vow, Faïence and Porcelaine were the prototype of the soon-to-come Ball Jointed pony species. They share the same vision than their mother on some points, and love her deeply despite her appearance.
Once they became adult, they made a itinerant monster exhibition and museum of oddities (which they love to collect), in their own train. Not only to travel around the world or bringing entertainement to everypony, but mostly to give a shelter to the "monsters" like them. The strange ponies of Equestria are all welcomed in their circus, to earn a new family and so escaping from normal ponies' cruelty.
The part of her body where you can see their woody layout is due to some lynching by normal ponies, they broke the ceramic.
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