Hello L.,
(sorry this got kind of long)
have him/her gargle w/ just plain water before going to bed and throughout the day (it will help loosen some phlem).
Go to sprouts or wholefoods they can point you to some of the products they have there.
--NO MILK... (whey, lactose, etc)
--Also, if your child is allergic to ragweeds... chamomile, echinacea, sunflowers, safflower and lettuce are ragweeds! so read every label of what he/she eats.
check the book: smart medicine for a healthier child (sprouts/wholefoods) it has lot's of great info about regular meds, herbal, homeopathic treatments. you can buy a used one at amazon.com.
Also if you have a fan w/ an ionizer... run it 20-30 minutes in his/her room before going to bed (I would not run the ionizer while they're sleeping)
~~peppermint oil
4 - 5 drops of peppermint oil on a paper towel in his/her room at night will help w/ the stuffy nose. **warning, do not apply directly to skin ... it needs to be diluted in a carrier oil first before puting on skin)
skip all the heavy chemicals at home. 1/2 alcohol + 1/2 water will do wonders... mirrors, counters, sinks, door handles, toilet seats.... that way you don't have to use bleach every time. like someone else said: audit all the things you use at home: dish washing detergent, laundry detergent, dryer sheets, etc. I have not used dryer sheets nor rinse on my clothes for a long long time. I also cut in 1/2 the amount of clorox I was putting on my towels. I also use essential oils to clean counters, sinks, etc.
Here are some links about essential oils:
note: I guessed some the spelling of these oils =)
http://video.google.com/videoplay?docid=8479435537623601064
~~cypress --cough, edema (soak your ankles and feet w/ cypress & epson salt) bronchitis, calming --very powerful against bronchitis!!!
~~cedarwood atlas
cough, calmin, anti-inflamatory, bronchitis, antibacterial, good for skin - renewing skin
http://video.google.com/videoplay?docid=6305768170638733228
~~eucalyptus smithy -- safe for 2yrs and older -- smells like valerian. great preventative. kills airborn cold and flu viruses
~~eucalyptus globulus - most popular - antiviral, antibacterial. too powerful - NOT FOR KIDS, not for frail/elderly people.
eucalyptus radiata - good expectorant. pulls things out of skin... like splinters, etc.
~~eucalyptus citradora (eucalyptus lemon) it is not 2 oils mixed! very powerful antimicrobial
very good bug repellant. very powerful antiviral/antibacterial.
essential oils kill germs
http://video.google.com/videoplay?docid=8960522012496686774
Good luck!