Do you have pics? Is both top and bottom skewed or just one or the other? I have two crossbeaks that are 13 weeks old. One is really bad- the top beak is 45 degrees from the bottom. The bottom is perfectly straight and she does just fine so far because she can still use her bottom beak as a spoon of sorts. If it was the bottom beak that was skewed, I could see that a chick might have more problems eating and drinking.
Lots of people here on the boards suggest making sure she has a deep food dish to eat from as she won't be able to peck tiny bits of food.
I think some people here will tell you to cull and some will say do everything you can for her. I would say (based on my really limited experience so far) to just watch her and if she's eating and drinking fine, just let her be. You may have to cull her down the road if she can't feed herself or if her crossbeak is just the tip of the iceberg for other congenital problems she may have.
Whatever you do, don't breed her. Some crossbeaks are congenital and some happen while incubating, but it may be hard to tell which is the case. You don't want to pass on that deformity. Good luck whatever you decide!
