Sorry she is battling with stuffy nose, etc. That sucks.
Around our house, we mostly try to eat healthy foods, avoid a lot of sugar, processed foods etc. We do have those in moderation, but we also eat a lot of healthy food, the girls love fruit, veggies, cheese, etc. I definitely agree on the getting enough rest. Abby gets about 10 hours a night.
When they even get a slight runny nose, we use this elderberry syrup
and they are usually better within a day or 2. We are rarely sick around here. I use this elderberry syrup
for adults on myself and my hubby and we recover quick as well. We add lots of vit C during those times as well. Abby can swallow pills, so when sick, she takes a 1000mg tablet of this brand
that is easy on stomach. Mimi usually takes 1 or 2 500mg chewables. Not sure if this all really works, or if we are just lucky, but we do it anytime we start to get sick and we don't get really really sick.
I also use a neti pot for myself and the girls (when they let me). It is great for those with allergies as well. It feels really good and I definitely feel like I am better quicker. I hate using medication unless necessary. This is the one
we use around here. We use the one that looks like a genie bottle. I discovered it when I got a sinus infection while pregnant and wouldn't take any medication and it was awesome.
We get our medications at Sprouts, but you can find it at most health food type stores on online at Amazon.
I would definitely check out the allergy theory as well. Allergies can often look like a cold.
Good luck getting her to feel better.