Sally Roberts made headlines in the UK after going on the run with her seven-year-old son in a bid to prevent him having the treatment, fearing the side effects.
The surgery went well, but now Sally Roberts is trying to stop doctors giving Neon anti-sickness drugs.
Earlier this week the former Auckland DJ’s bid to prevent him having more cancer treatment was dismissed by a judge.
It was reported by the Daily Mail that she failed in an attempt to get legal proceedings surrounding whether Neon can receive radiotherapy adjourned after the High Court heard her expert could not even spell the form of the disease he is suffering from.
She had originally wanted any operation delayed until more doctors had been consulted.
The Family Division of the High Court in England was told that Neon needed brain surgery before radiotherapy.
Without it, he would die.
He had already had surgery once and was awaiting radiotherapy when he mother took him on the run.
At the weekend, Sally Roberts and estranged husband Ben Roberts were told that the cancer had returned, with a 1cm mass revealed in scans.
The Daily Mail said Roberts had initially consented to Neon having the treatment, but then changed her mind.