Semi-royal relatives? (3)
I believe the answer is:
kin
'relatives?' is the definition.
(kin can mean relatives or family)
'semi-royal' is the wordplay.
I cannot quite understand how this works, but
'royal' could be 'k' (abbreviation for king) and 'k' is found within the answer.
The remaining letters 'in' is a valid word which might be clued in a way I don't see.
This explanation may well be incorrect...
Can you help me to learn more?
(Other definitions for kin that I've seen before include "Group of relations" , "Family and relations" , "One's family/relations" , "Flesh and blood" , "A person's relatives, goes with kith" .)