When I have a cold I get vitamin C and Zinc Lozenges from a health shop but they might do something in liquid form or you could melt them down with hot water? Echinacea and Goldenseal tea is also very good and obviously lemon, ginger, cayenne pepper, cinnamon, warm ribena etc
Fruit smoothies are very good for fighting off colds aswell. The best things to use are orange, pineapple, grapes, banana, pink grapefruit, cantaloupe, pears and apple cider vinegar.
My nan swears by chicken soup with garlic, basil, thyme, oregano and rosemary.
Get a vapouriser and make a mixture of olbas oil, lavender, tea tree, peppermint, spearmint and eucalpytus oil. You can also use the mixture in the bath.
Apparently you shouldn't have anything sugary including juice as it reduces the immune function but I've always used honey in cold rememedies and also blackberry jam (honestly it does make you feel better) so think I will ignore that.
Also prop up the end of her cot with some books or bricks. It will make it easier for her to breath.