It's not a family story.
( It ( ( ( 's not ) ( a ( family story ) ) ) . ) )
(ROOT (S (NP (PRP It)) (VP (VBZ 's) (RB not) (NP (DT a) (NN family) (NN story))) (. .)))
It's a story about drugs and murder.
( It ( ( 's ( ( a story ) ( about ( ( drugs and ) murder ) ) ) ) . ) )
(ROOT (S (NP (PRP It)) (VP (VBZ 's) (NP (NP (DT a) (NN story)) (PP (IN about) (NP (NNS drugs) (CC and) (NN murder))))) (. .)))