Another group which I listen to recently is Vox Angeli. I found it while I was searching French song in YouTube. So this is what they say on their official site: Vox Angeli: Le Site de Officiel.
What it say is about like this ( I translated it using my weak French, so please tell if there's mistake). " Vox Angeli is composed of 6 children, aged between 10 to 13 years old..."
The children are Claire Conruyt, Etienne Girardin, Iris Lambert, Lola Beris, Louis-Alexander Desire and Mathis De Ruyver. What I say is that they have nice voice just like Jean-Baptiste Maunier.