Maybe everything about discretion you know it will perhaps come in handy?
“Discretion” is defined as “the freedom to decide what should be done in a particular situation”.
So the source of this message, let’s say a movie producer, is advising that parents should decide whether or not their children can watch the movie, as opposed to the movie producer explicitly stating yes or no.
parental discretion advised
It means that children are allowed to watch a movie or TV program, or take part in an activity or game depending on the discretion (judgement) of their parent(s).
Example : Maybe there is some violence in a particular movie, and the parent thinks their young child would find it too scary to watch. They may use their discretion and prevent the child from seeing it. On the other hand, if they think the child is mature enough, they may use their discretion to allow the child to watch.