[Flabbibulin]

In my opinion, the "unwilling or unable" part really should be clarified if you are hoping to get some public donations, because if it is unwilling, then who the hell are we, as complete outsiders, to contribute to a custody battle? If the father is simply unable financially to send the kids back to Canada, but is otherwise ok with them returning here, then yes I would be happy to contribute.

If the father is unwilling in sending the kids back to Canada (for whatever reason), then perhaps a better course of action would be raising funds for your daughter to at least go to Australia for an extended period of time so she can visit and be with her children while the case plays itself out through legal channels.