It's hatch day and I need advice, please.

[3riverschick]

Hi,
It's hatch day and I need advice, please. Went out to check on my Light Sussex pullet. There was one egg in the bottom of the coop. Rooster had not bothered it. Been kicked out of the nest. It had one deep peck in it which went clear thru the shell. It was cold. Took it inside and opened it up. Lovely perfectly formed chick inside...except it's intestines were on the outside. It was dead.
What is the pullet doing? Is she triaging her eggs so only the healthy hatch? Do chickens do this? Did she peck thru the shell to figure out why this egg felt "different"? She has been nailed to this nest for three weeks. If she ever got off (I am sure she did to eat and poop) I never saw it. Her sister is sharing the nesting box with her to keep her company but not sitting eggs. Do I worry? Just leave them alone?
Thanks for any advice.
Best,
Karen

 

[red golden]

I would say it was an accident and wouldn't worry unless she kept doing it. The pecked hole could have been curiosity.