Tucked tail feathers

[mk4lh]

I'm a new chicken mama to 26 barred rocks. They are almost 3 months old. They have plenty of pen room, plus they get yard time when I'm home to keep an eye out for predators. My question is; I have one hen that seems to keep her tail feathers tucked all the time. Is this because she is the most submissive of them all? She eats, drink, poops, and free range along with the rest of my girls. Thank you for your answers.