Ive had a chicken show up the morning after a dog attack, but frankly, not many. Its possible but dont get your hopes up.
Its almost certain it is the same dog. Thats just too much of a coincidence. Legally you didnt see it though and that makes a difference legally. Would your neighbor be able to testify it was that ladys dog? Definitely talk to that lady about her dog. You know it was her dog chasing them in the morning.
I dont know what the laws are in Missouri. In Arkansas and Oklahoma you have a right to protect your animals if they are being threatened or harmed. But you do not have the right to shoot or harm a dog that enters your property unless it is causing damage. Several months back two coon dogs treed a coon on someones property just over in Oklahoma. He shot them. They were not threatening him, his family, or his property. He had to post a $15,000 bond to get out of jail on an animal cruelty charge. If they had been threatening his family or his animals hed have been OK, but they were not.
If you do take drastic measures, grab a camera and document the damage. Protect yourself legally. If she is unresponsive when you talk to her or if you have another experience, it might be a good idea to report it to law enforcement, especially if you can identify her dog, just to get it on the record. If you get lucky, a cop may chat with her and let her know what you can do to the dog plus she would be responsible for damages. Sometimes its remarkable what a chat with a cop can do for some peoples attitudes.
You are innocent. Through no fault of your own, you are being put in a very tough position. You may feel like you are the bad guy or she may treat you that way. You are not the bad guy. That lady is probably not a bad sort either but she has a responsibility to control her dog.
About three years ago, an elderly neighbors husband died. Her granddaughter gave her a pup to keep her company. That pup roamed all over. It chased cows and calves and horses. I ran it off once from chasing my chickens. When I mentioned it to her son, he said shoot it next time. Really? Shoot a grieving widows pup? Her granddaughter is the one that takes care of my chickens when Im gone. That pup disappeared a few days later. I think her son or her nephew who lives in this valley took care of the problem we were all having. I honestly dont know if I could have shot that dog or not.
Some people may tell you to SSS, shoot, shovel, shut up. In some circumstances that can work real well. Ive shot stray dogs that were killing my chickens before. Didnt enjoy it but I did what I had to do. Where I live I can SSS. Neighbors arent that close and a lot of people around here target practice. If a neighbor told you that a dog was in your chickens, it sounds like you might be able to shoot and shovel, but you might have trouble with a neighbor handling the shut up. Thats why it may be important for you to document and report.
Good luck! Ive been there. Its not pleasant.
