increase children's antibodi??

I wonder how I can boost up my kidz antibodi. hmm.. adakah ummi perlu leave it to nature? nature healing... or need to eat something? or need specific exercise. Let me list all the alergi faced by amirah and thoriq:

1. alah pada jus oren/semua yang ada kaitan dengan oren. effect : tekak akan merah = demam, so definitely NO for vitamin C tablet oren, scott's emulsion oren (which is quite yummy than the white one,urghh), sunquick oren etc
2. alah pada air batu/minuman berais. effect : tekak akan merah=demam/batuk/selsema/pneumonia. then definitely NO for aiskrim(which all kidz love!), air sejuk, etc
3. alah pada kelapa. effect : batuk/selsema/pneumonia. then definitely NO for all product of kelapa which is banyak khasiatnya ie air kelapa/natadecoco kelapa, coconut shake, minyak kelapa etc
4. alah pada makanan berkandungan gula tinggi. effect : tekak merah=demam. then definitely NO for air berkarbonat, VITAGEN, RIBENA , air kotak, etc
5. alah pada makanan pedas. effect : tekak merah = demam
6. alah pada seafood (jika kadar pengambilan tinggi) . effect : selsema/ruam

hmm, apa yg perlu ummi lakukan ye? nak beri vitamin C, tak boleh. scott emulsion pun tak boleh. So, macam mana nak boost up antibodi anak-anak ummi ni? Ya Allah, help me for what I dont know. Show me the way to give them a good health...