A woman who does not want her seven-year-old son to have radiotherapy treatment following surgery on a brain tumour has renewed her High Court fight.
Sally Roberts, 37, of Brighton, East Sussex, fears radiotherapy will cause her son, Neon, long-term harm.
Doctors say Neon might die within months without radiotherapy.
A High Court judge began hearing more evidence about the pros and cons of radiotherapy.
Earlier this week, Mr Justice Bodey ruled that Neon could have further surgery against Ms Roberts' wishes.
Ms Roberts, who comes from New Zealand, wanted a second operation to be delayed until more doctors had been consulted.
But specialists said follow-up surgery needed to be carried out urgently.
And Mr Justice Bodey said the operation should go ahead.
A doctor treating Neon told the judge that the operation went well.