While you're technically a child until you're 18, I don't think sending a song from your teenage years is in the spirit of this spin-off and should be discouraged in my opinion. However, I asked Steffan about a cut-off age and he didn't have anything in my mind.
I personally think for this spin-off that child should mean 10 years and younger.
I personally think for this spin-off that child should mean 10 years and younger.