Ethel is my ~3 year old female duck that has had issues with soft shelled eggs in the past. This year we started her on pellets with calcium and find that it's helping a lot. Not only is she laying more but they are mostly hard shell. That being said she does have an odd soft shell, maybe 3 so far this year (in between the hard shells). Now though, when she lays those soft shells they have an odd tail growth attatched at the end. The tail itself often appears out of her vent first and she usually lays the rest - but today she didn't. While I was attempting to inspect her she ripped the "tail" off the egg. At this point I'm concerned about the yolk leaking inside of her and causing havoc. I put her away for the night hoping to spur her to lay because if she's out she's on the go and doesn't want to stop for anything. Tomorrow morning I'll inspect her better and see if she passed the rest of the egg. I guess at this point my question is: if she hasn't passed the egg do I attempt to "help" her? Gloves and ky jelly? I also read something on this site about flushing her with a mild vinegar/water solution? Also if I am worried about peritonitis what kind of antibiotic should I be looking at and is something like that avaliable at a farm and tack store (say tractor supply)?