Brennigan is it possible an egg got stuck? Is that yolk? Otherwise watch to see that your other two have no eye/ nose dishcharge, combs are full colored, and that everyone's poops are normal green with a white cap. No frothy ones; cecal poops of course will be the runny brownish which is normal. As to the grieving process, yes her friend is calling for her. They might need extra treats and encouragement for a while as they sometimesgo "off their feed". It will be realky hard to add as the other two are gonna terrorize any newb. It is because it is a small group, and they aren't free range. Not a bad thing at all but it makes them more territorial. My trick is to put food and water everywhere and to add buckets and whatever i have around to clutter the space and provide a foil against attack. This being your first add-on you must remember any adds can silently bring sickness too. And if yours picked anything up it will show itself now anyway, as they just lost a buddy. Watch, see if you have any sickness already, and either wait until spring or do any adding before the deep cold snap so if something crops up it will not be as severe.
(Novel) lol
(Novel) lol