WITH the Hong Kong Down Syndrome Association suffering much misinformed hostility in recent weeks, the charity has been in need of a major publicity coup to propel it back positively to the public arena. Enter Sarah, the Duchess of York, to the rescue. Later today she will fly into Hong Kong for a visit to the troubled association's centre in Tung Tau Estate, Wong Tai Sin, tomorrow. And at night she will be the principal guest at an exclusive black-tie fund-raising dinner at the China Club, hosted by the charity's chairman, David Tang, who has been instrumental in persuading the duchess to visit the territory. It will be Sarah's first visit to Hong Kong and, according to her Lady-in-Waiting, Christine Gallaher, with whom Keeping Posted took tea yesterday, the duchess is quite excited about the trip since it's one place she has always wanted to visit. Ms Gallaher, who has worked with Sarah for four years, arrived here yesterday from London to liaise with government officials and the police to ensure the visit runs smoothly. The duchess, estranged from her husband, Prince Andrew, will be arriving from Australia with their two daughters, the princesses Beatrice, five, and Eugenie, three. In between her commitments with the Down Syndrome Association, Sarah will also visit the centre run by Youth Outreach (a charity working with teenage runaways) at Chai Wan. Co-incidentally, Sarah - who has always taken a keen interest in the welfare of underprivileged youth - visited a similar centre in Wales just before Christmas. Hopefully the visit will help to establish the duchess as a caring royal who is keen to use her position to help those in need. With the two princesses in tow, it certainly won't be all duty for Sarah. We're sure they'll want to do some sightseeing. But it will be tight. The duchess and her daughters leave Hong Kong on Friday.