Relatives making awful scene about one (6)
I believe the answer is:
nieces
'relatives' is the definition.
(I know this)
'awful scene about one' is the wordplay.
'awful' indicates an anagram.
'about' indicates putting letters inside.
'one' becomes 'i' (Roman numeral).
'scene' is an anagram of 'neces'.
'neces' going around 'i' is 'NIECES'.
'making' is the link.
(Other definitions for nieces that I've seen before include "Relatives of 27dn" , "Young female relatives" , "Scene I set up for relatives" , "Relations" , "They're related" .)