What does “the sand don’t stray far from the beach” mean?

"The sand don’t stray far from the beach" is a play on the saying "the apple doesn’t fall far from the tree." Both expressions imply that someone or something tends to closely resemble or inherit qualities from their origin or source.

In the context of "the sand don't stray far from the beach," it means that a person's behavior or characteristics are predictable or consistent, closely resembling or reflecting their upbringing or environment.