Close relative runs into trouble (7)
I believe the answer is:
brother
'close relative' is the definition.
(I've seen this before)
'runs into trouble' is the wordplay.
'runs' becomes 'r' (cricket abbreviation).
'into' indicates putting letters inside.
'trouble' becomes 'bother' (synonyms).
'r' put into 'bother' is 'BROTHER'.
(Other definitions for brother that I've seen before include "Male sibling" , "Eg, monk, friar" , "Relation" , "Trade unionist" , "Union member - male relative" .)