Affair giving rise to trouble with one lad (7)
I believe the answer is:
liaison
'affair' is the definition.
('liaison' can be a synonym of 'affair')
'rise to trouble with one lad' is the wordplay.
'rise' says the letters should be written backwards.
'to trouble' becomes 'ail' ('ail' can be a synonym of 'trouble').
'with' is a charade indicator (letters next to each other).
'one' becomes 'i' (Roman numeral).
'lad' becomes 'son'.
'ail' back-to-front is 'lia'.
'lia'+'i'+'son'='LIAISON'
'giving' acts as a link.
(Other definitions for liaison that I've seen before include "Sort of officer" , "Contact between groups" , "Mil. coordination; illicit affair" , "Collaboration" , "Communication between people or organisations" .)