Managed to come up with cryptic clue in such a family? (7)
I believe the answer is:
nuclear
'such a family?' is the definition.
(nuclear family is a kind of family)
'managed to come up with cryptic clue' is the wordplay.
'managed' becomes 'ran' (I've seen this before**).
'to come up' says the letters should be written in reverse.
'with' means one lot of letters goes inside another.
'cryptic' indicates an anagram (I've seen this in other clues).
'ran' back-to-front is 'nar'.
'clue' is an anagram of 'ucle'.
'nar' placed around 'ucle' is 'NUCLEAR'.
'in' acts as a link.
(Other definitions for nuclear that I've seen before include "and 6 Down: Power producer" , "one's immediate family?" , "Type of energy" , "Sort of energy" , "basic family" .)