forbidden fruit

bear fruit

To produce good results; to yield benefits; to succeed.

fruit of one's loins

One's child or, collectively, one's children or descendants.

fruit of the poisonous tree

Evidence that has been obtained as the result of an illegal act on the part of law enforcement personnel (such as an unlawful warrantless search, or continued questioning of a witness who has invoked the right of counsel), and which is therefore excluded from being admitted as evidence in a trial.

fruit of the union

A child, especially from a marriage or similar union.

fruit up

To grope a young boy.

low-hanging fruit

Easily obtained gains; what can be obtained by readily available means.