My 19ms old daughter has the same problem as yours. She will be sick once or twice a month, usually flu or upper respiratory infection. The latest two visits to family clinic were for sore throat which eventually led to intake of anti-biotics because of fever for two days. I guess its partly because of the poor air quality in Lam Tin and partly because she attends playgroups three times a week. Of course she may be weaker than other bbs too. I have already brought her to the podium downstairs for walking / running / playing everyday but it doesnt make her stronger. I have read some articles and concluded that the most effective way to help her fight against virus /germs is:
1. Wash hands often
2. Drink more water
3. Have enough rest
I want to stop A/C too but its too hot now and no wind in my flat (blocked by other buildings). She cant sleep well if w/o A/C.
My daughter has already received all necessary vaccination.
The only fortunate side is, so far she has no serious illness and has never been to hospital. I dare not to let her recover by herself even if just minor flu because BB's illness at this stage can be complicated and developed into serious problems quickly.