I agree, check your agreement that you signed with them. If there is no agreement I'm sure they would remove it if politely requested by you.
In Australia, there is no specific law which prevents the unauthorised uses of your image or right to "privacy" per se. In addition, the photographer will likely be the owner of the copyright in the photo, and has the right to deal with it as he or she wishes because he or she created it.
There are options to sue for defamation - if the photo pictured you or your family in a derogatory way and lowered you in the eyes of the public or alternatively, misleading and deceptive conduct if you are a celebrity or well known in the community and the commercial use of the photograph affiliates you with a particular brand that you do not in fact endorse. Its an action based on the misappropriation of your reputation.
Apart from these things, which do not appear to apply to you, your best bet would be to politely request that they remove it.