She is way smaller than the other chicks, and they all hatched on the same day.
This may not be the same problem, but I used to worry myself sick about Latte because she was so much smaller than the rest. It turned out I had a brooder full of boys and one girl.
Your chicks are still pretty little. Little chicks sleep a lot. Latte was my "sleeper" and I think it may have been because the boys were so spunky and always ate first. My current brooder - the same thing is happening. The chicks that I think are boys eat before the girls. The poor girls have to wait. "Ladies first" doesn't seem to happen in the chicken world.
Someone else mentioned letting her have electrolytes separately. I would do that. Maybe also offer her chick feed separately, too.
Also - very important at this age - check for pasty butt. Pasty butt can kill a chick. I almost lost my hatchery RIR when I was a new chicken mama because she came home from the feed store with pasty butt. She was a pretty weak little girl until I gave her bath and dried her off well. After that, she thrived.
I really hope that your cute little Hope is OK.