you might not have yet discovered that daycares/creches basically do not exsist in hong kong. there are a very few places are day cares, but they are aimed towards low-income (if you are in olympic, then i'm guessing you wouldn't qualify) and they generally have a long waiting list.
baby sitters are also VERY uncommon as most people resort to hiring a helper. you could try rent-a-mum for a legal alternative.