My kids like to watch the channel vlad and niki on YouTube. The parents make between 45 and 60 million dollars a year off their YouTube channels which exclusively feature the children. They seem like sweet kids but they must spend a lot of their time filming all these videos. They have action figures of themselves. They live in the lap of luxury and want for nothing materially but i don't think even if i knew how to make these videos etc that would make me use my children to make money. Those videos will be there forever.
Vlad and niki are the two older children and they seem to be featuring less but the parents have had two younger children and the majority of the newer videos seem to focus on the two little ones.
The cynic in me says that maybe the older children have had enough of it, so that's why they're not doing it or maybe they're not "cute" enough now they're pre teens as the target audience is small children.
Would you do it for millions of quid? Could be argued that they're not doing anything actually harmful to the children so why not if it means the children end up rich beyond their wildest dreams.