Around 7 PM today I realized that my beautiful RIR girl is missing. I just fed them around 6 PM, and she was still around. Usually around this time my flock would go to the area near their coop. We have two houses on this lot, a front and a back house. I live in the back house, but their coop is behind the front house. I was in my kitchen, but I also went to the coop a few times. The coop is about 50 feet from my kitchen and can be easily seen from where I was. I didn't notice any loud noise or anything unusual. When I checked on them, I saw they were around the coop area eating grass. When some of them started getting on the roost, I noticed my Katie is missing. I am trying to figure out what happened because they seem fine and calm. My property is fenced except the gate is missing for the driveway. They usually love to go to the front yard of the front house where there is a lawn with grass. I think Katie might go to the front yard to eat some grass and might even go the sidewalk area with a little grass. At first I thought she might wandered off and went to the street and got lost. But most of the time they have only stayed within my property line where the fence is. I have seen Katie went to eat the grass in the side walk just 3 feet from the fence, but I don't think she would wander off by herself because she is scared and knows it is not safe there. I walked the streets around my house looking for her calling out her name. Then I think she would not wander and get lost because it was around the time for them to go to bed. I think she might be picked up by someone walking by and saw her standing near the fence or in the sidewalk in front of my house. It was still light so I don't think there were many predators. If it was a hawk, I don't think my other chickens would be so calm. Then I thought what if a dog came by, but then there would be noise. The main thing that seems odd is that my other chickens and roosters are so calm. They don't make any noise when they go to roost. They don't look for her or do they know she is missing. I have eight hens 8 months old and two roosters at same age. I am just so sad because I know how awfully scared she must be, and I pray that she is fine somewhere. Thank you for any advice.