Relative getting drug in French resort (5)
I believe the answer is:
niece
'relative' is the definition.
(type of relative)
'drug in french resort' is the wordplay.
'drug' becomes 'e' (E is another name for ecstasy).
'in' means one lot of letters goes inside another.
'french resort' becomes 'nice' (French coastal resort).
'e' inserted into 'nice' is 'NIECE'.
'getting' is the link.
(Other definitions for niece that I've seen before include "[PRIEST'S] daughter?" , "A sibling's daughter" , "One of the family" , "Criminal" , "Son's cousin" .)