Kin, I use nan bei xing quite a fair bit. Use as whole kernels, not pounded. Honey dates too, quite often. Chuan bei and orange peel probably once a fortnight? Or maybe less. Again not pounded. For soup, no need to pound. The chinese pear, chuan bei fen and nan bei xing, I only double boil when I "sense" one of the kids coming down with something. As for quantity, haha, it's all "agak-ration". But yeah, probably a handful of nan be xing for a pot of soup for 4 pax. Another good herb for cough is something that looks like a squashed mandarin. Sometimes I use that with chuan bei, nan bei xing.
Chinese soup and herbs serve to strengthen from within so it's a slow process. Must just keep on with it to see the rewards at the end. Anyway, soup always very nourishing so I make sure the family gets at least 4-5 rounds a week. And it's easy to prepare.
Kids tend to fall sick with the common cough and cold quite frequently during the first few years, but around 4/5 onwards, it gets less frequent. I remember my daughter was down quite often during the first few yrs but since K1, she's only been down with a cold once or twice. My friend's kids better still, since young, if they catch a cold or cough, it'll only last for a day or two, then gone! She gives them homeopathic tablets. I tried that too, it will work right at the start of cold and cough. And I think it works hand-in-hand with western medicine. I use it to complement med from doc and I think it speeds up the recovery.
Kin, are the girls enjoying the enrichment class @ YKids?