that's not good; I'd try to remove it asap. The moisture could compromise the bloom on one or more of the eggs.I gave her a piece of melon and checked on her a few hours later and she eaten a bit of it and then tried to tuck it underneath her
In general it is not wise to feed a broody on the nest. She will get off to eat when she is hungry. Just make sure there is good food available for her when she does. And clean water. And a dustbath.