Descendant, offshoot (5)
I believe the answer is:
scion
This clue is a double definition.
'descendant' is the first definition.
(I know that scion is a type of descendant)
'offshoot' is the second definition.
(I've seen this in another clue)
(Other definitions for scion that I've seen before include "Offshoot" , "Young child" , "Young shoot or twig" , "Young family member" , "Young shoot/twig" .)