When comes to gambling and children, all countries with a minimum of civility will have laws which will forbid children from partaking in gambling, there is no doubt about it, the debate would be whether it should be illegal for a minor to also witness gambling activities being carried out by others.
Even though online casinos do not have an age limit, of course parents will not allow their children to gamble even if they are born into a very rich family because gambling is not something that should be learned either for example, there are other people who gamble and there are other people's children, I don't think the people who gamble will show the gambling they do, therefore if there are parents who gamble and allow their children to see it it is probably the parents who have taught them wrongly even though they have good intentions behind it I don't think it makes sense.