It's a case of choosing your priorities isn't it? If you wanted to go you would find a way to make it work even take a part time job as someone else suggested, but if you don't want to go then apologise to the couple and celebrate with them in another way such as treat them to a meal out.
I do feel I ought to stick up for Hong Kong especially as Expat has made it sound like an utter shithole (!!), IME it is a brilliant place to go on holiday! Maybe you need the insiders view of Hong Kong instead of the tourists view...
The city is brilliant, especially at night time, there are plenty of places to go shopping or just browse at the markets particularly in Mong Kok, the Ladies Market, the bird market and more.
The city skyline is one of the best views in the world from The Peak after a scary trip up the Peak Tram, and you can also explore the mountain and gardens around The Peak.
If you also visit Tsim Sha Tsui, you also get amazing views and can see the harbour, plus catch the famous Star Ferry!
Ocean Park and Disneyland are also fun days out for the whole family. Ocean Park had two gorgeous pandas last time I was there, and you can easily spend a whole day at the park.
You can take a trip to see the Big Bhuddha on Lantau Island and take an unforgettable trip in the cable car that goes accross the sea and mountains.
You can visit the beautiful sandy beaches at Sai Kung.
If you enjoy the countryside there is plenty in the New Territories and some huge butterflies to be seen and waterfalls.
Cantonese people love children and will make a fuss of them. The food is fresh and delicious, so much to choose from.
Just to add I'm not working for their tourist board ;-)
Anyway, I'm off there in a few weeks with 9 month old DS and DH and I cannot wait!!!