What do you mean children are deeply rooted?

In many ways, it depends on your understanding. You can't end a problem hastily.

1: As the common people say, marching at an early age must be deeper than other children. Now it is: I have been studying since I was a child, and I must have started earlier than other children, with a deep foundation.

2. Officialdom: This child has deep roots and good family background (generally not ordinary people).

There are many possibilities, depending on which way to say that the foundation is deep. The above two are just common.