Ashya King's older brother Danny has said he is "thrilled" that his parents have been reunited with their son.
I am thrilled. I just want to thank everyone for helping this become a reality. Now I just want to get some rest and help Ashya get better.
Ashya King's parents told the Daily Mail they fled the UK after being told NHS treatments would leave him with life-long disabilities.
The head of the police force which applied for a European Arrest warrant against the parents of Ashya King has now urged their release.
A British mother whose son's life was saved by proton therapy has told ITV that she defied NHS doctors' advice to pursue the treatment.