Just like the majority of the mutant population Kaylee lost her powers years ago and was forced to adapt to a new reality.

On the tall side, standing about 6 foot, Kaylee still looks a lot younger than her age would suggest and weights a lot less than she should. The benefits of having enhanced healing for most of her life and hollow bones which obviously didn't care her powers were not there anymore.
Her large wings are gone, replaced by some scarring on her back where they used to connect and so is her seemingly unlimited stamina gone.

A pretty mean case of "Life sucks" if you ask her but after wallowing in self pity for many many months she's trying to get back on her feet.