I actually went to small claims court for a situation just like this. Parents gave money but "changed minds". I actually ended up winning in court. You do not need to give the money back and if they have an issue with it they can take you to court (for such a small amount they most likely won't so don't even worry about that as I am the one who took the family to court). If you need some more info and need advice feel free to send me a message.