Questioning a small family group, to start with (6)
I believe the answer is:
asking
'questioning' is the definition.
(I've seen this before)
'a small family group to start with' is the wordplay.
'small' becomes 's' (abbreviation - e.g. clothes size).
'family' becomes 'kin' (synonyms).
'to start with' suggests taking the first letters.
The initial letter of 'group' is 'g'.
'a'+'s'+'kin'+'g'='ASKING'
(Other definitions for asking that I've seen before include "Direction a question" , "Presenting petition" , "Inquiring" , "Making request" , "Questioning" .)