How close does a sprite need to be in order to be classified as a "neighbour"?

How does the "my neighbours" block actually work?

I'm wondering too

OK (Post must be at least 4 characters)

Do an experiment! Have a sprite move toward another sprite and keep asking for its neighbors, and tell us when it gets close enough.

I just do okay because it's 4 characters long.

that's dependent on the size of the sprite whose neighbors are requested.