Cost to protect new member of royal family (6)
I believe the answer is:
prince
'member of royal family' is the definition.
(prince is a type of royal)
'cost to protect new' is the wordplay.
I cannot really see how this works, but
'new' could be 'n' (common abbreviation eg NT for New Testament) and 'n' is found in the answer.
'cost' could be 'price' (synonyms) and 'price' is located in the remaining letters.
This accounts for all the letters.
This may be the basis of clue (or it may be nonsense).
(Other definitions for prince that I've seen before include "King's son" , "Machiavellian ruler" , "Son of a royal house" , "Panto character" , "Sovereign's son" .)