Sophie, who turns three in March, was diagnosed with autism four months ago.

Since then, the Wilsons have spent more than $7000 on treatments, many of which are only minimally funded by the Federal Government and are not covered by private health insurance.

The most successful available treatment for autism is applied behaviour analysis (ABA), an intensive program that teaches communication skills and appropriate social behaviours through repetition and reward. The best results are achieved with full-time treatment of up to 40 hours a week.

However, most parents are only able to secure a few hours a week with a therapist under a Federal Government program, which is not guaranteed past 2010.

While the Wilsons have had to put their dream of home ownership on the back burner to pay for full-time therapy, Mrs Wilson said it wasn't a tough choice to make.

"We're very lucky because most people go without ABA.

"We want to give Sophie the best possible chance in life and the difference we've already noticed in her has been astonishing.

"Her vocabulary has more than doubled, she's learnt how to say please and thank you, how to share and how to respond to other people. She doesn't throw as many tantrums as before."

Mrs Wilson said ABA could cost between $20,000 and $40,000 a year, not including paying other specialists such as speech pathologists and psychologists.

She said the family claimed four different rebates from the Government - including Medicare, Centrelink and a child-care rebate - but it "nowhere near covered the costs" involved.

Mr Wilson urged the Government to continue funding the program and to provide comprehensive treatment programs to all children with autism.