I will let my "small" boy study 1/2 day nursery in Feb 08 (2nd term only) coz I do want him to learn "group" life, vv and eat by himself instead of wasting time at home with bunbun to watch TV when we go out work. But, it's true that baby will easily get sick like my "big" girl. So, think 1/2 yr is enough to just get a start b4 K1.