Americana with low tail

[Organa farm]

I have a flock with 12 hens. None of them have started laying yet. And two of them are americanus one of my americana‘s is perfectly normal and always has her tail up. My other americana has a low tail, she acts normal and gets along with the others just fine she eats drinks and runs just the same as the others, but I was wanted to know, should I can be concerned about her never raising her tail feathers.

In the photo you can see both of them that is how they hold there tails none of my other chickens do this.

 

[Wyorp Rock]

americana has a low tail, she acts normal and gets along with the others just fine she eats drinks and runs just the same as the others

Eats/drinks/acts normal/runs just the same as the others...
Sounds like she's o.k. to me.
Some birds are just built a bit differently than others. I wouldn't worry unless she starts to act like she's sick.