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 string like soft shell "growth" attatched at the end. The "string" itself often appears out of her vent first and after a time she lays the rest. She currently has a eggy "string" hanging out of her bum. My question is; do I leave it there and let her pass it on her own? Or to I attempt to remove it? And also any idea what causes this? Is it normal? Thanks in advance!