Riotous glee in a family (7)
I believe the answer is:
lineage
'family' is the definition.
(I've seen this before)
'riotous glee in a' is the wordplay.
'riotous' is an anagram indicator.
'glee'+'in'+'a'='gleeina'
'gleeina' with letters rearranged gives 'LINEAGE'.
(Other definitions for lineage that I've seen before include "Genealogy" , "The strain" , "Descent (from an ancestor)" , "Ancestry, sequence of descendants" , "Descent from ancestors" .)