I have primary care of our son, 15. Ex-wife has primary care of daughters 13 and 9 ( custody of children). I pay her the Human Services prescribed weekly child support agreement amount directly. No issue there. But I also make payments for private school fees and uniforms, medical expense and out of school activities that represent an additional 50% of the value of the CSA figure. I understand I can only declare the CSA prescribed figure on my tax return, as this is the "Child Support" as agreed, but does my ex-wife have to declare the extra payments anywhere, so that Human Services are aware of my contributions? I would have thought cash payments to her for these items are just another income stream that should be factored in when my future child support payments are assessed, but if she fails to declare them, there is no formal way that money is recognised.