How come Yuki Onna turn into a kid? Lord Second Era

As seen in Episode Number 8, during Gyuki's flashback, Yuki Onna can be seen as a woman with both adult facial feature and height.





Lord Third Era (Now, Episode 1-...)

Now, Yuki Onna is as tall as human form of Sandaime and has kid-like facial feature, which is kawai :D.





HOW COULD THIS HAPPEN?

NOTE: I am asking HOW not WHY



Although unrelated, the reason why she did this might be something like this:
Those are two different Yuki Onna. The one that appears in the first picture is the mother of the one that appears in the second one. If you read the manga, it is explained in further depth there. (Sorry I forgot their names since it was a long time since I read the manga.)