Collecting Children's Voices - Question for Mozilla Legal

Hello everyone!

The CV Terms state that “Common Voice is open to anyone over the age of 19. If you are 19 or under, you must have your parent or guardian’s consent and they must supervise your participation in Common Voice.”

How exactly is that accomplished for underage persons? Is there a consent form that parents / guardians must sign? Or does CV simply not accept children’s voices due to legal and other issues (such as possibly unappropriate content in the sentences to be read)?

I’d be grateful for any info anyone on the Mozilla legal team could provide on this matter.