With 'Ysela' it was entirely Jae'si's idea. She's the type of parent to try to come up with a super 'unique' name and settled on a partial anagram of 'Ysayle' in hopes Estinien would like it.

With 'Y'onah', despite Y'shtola not being incredibly in touch with her tribe, she still preferred a name in keeping with their traditional conventions. She would not say so outright, but Jae'si picked up on her tells enough to gather that's what would make her content.

Between both their last names, Jae'si opted to have both her daughters keep the surnames of her respective partners (Ysela Varlineau and Y'onah Rhul). 'Malheur' is not Jae'si's birth surname, and so it didn't feel right to have either child take it.