Does anyone else have a "narcoleptic" chicken?

We added some new birds to our flock a few weeks ago and accidentally introduced what I believe to be IC. I've treated and will keep my flock as they have good quality of life, not sure if it has relevance but i figured I'll mention it if it helps. We have a bielefelder pullet (about 3-4 months old) that's always sleeping. She'll be foraging for food with the others totally normal then just lay down and nap wherever she is. She eats, drinks, runs, flies, and aside from the sleeping and from how insanely gentle she is, she acts totally normal. I go to hand feed the flock and everyone else will peck my hand so aggressively but you can't even feel her take the food, she's that relaxed. She's the only one in the flock who is like that and I guess I'm looking for advice to see if anyone else has had a bird similar and if they're sick at all. Maybe it's just my anxiety but she seems way too calm and I can't help but feel like one day I'll go to shake her awake and she'll just be dead