in NSW you can also go to Selwyn slopes. It is a small resort that is very family and beginner friendly.
From qld there is no reason not to go to Victoria instead. Falls creek claims to be closer to Brisbane than the big NSW resorts.
You can hire clothes there and I think you might know someone with some kids clothes you can have...
We're at Jindy and Perisher most weekends.
If you happen to stay at Jindabyne mid-week I know a really cheap place you could stay....