Would you say shes on drugs!?

My neighbor is cousins with my cousin **** and she lives next door to my grandma my cousin helps my grandma out a bunch I'm blessed to have her living next door to my grandma!! But my neighbor had told me she is smoking crack she had been on drugs yrs ago and got help but she had told me she goes on binges and my grandma had told me my cousin always has no money but she makes good money and that is only why I had told my grandma that's what my neighbor had she's on drugs and my grandma won't belive me and I'm afraid my grandma is giving my cousin money behind our backs been talking to people about it and I'm not getting any soultions on what to do! My grandma says no way she doesn't but she really doesn't have a clue and I'm not sure even if its true bc its all hear say! Anyone has any advice?