Seven-year-old Neon Roberts is making "good progress" following his treatment, his father has said.
Late last year, Neon's mother Sally, failed in a legal bid to stop her son having radiotherapy for a brain tumour.
The High Court ruled that Neon should undergo radiotherapy for the cancerous tumour against her wishes.
Neon's father Ben - who is separated from Ms Roberts - said his son had completed the course of radiotherapy as planned.
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