The one with the nest in which there were chicks? (6,4)
I believe the answer is:
family tree
'the nest in which there were chicks?' is the definition.
The answer and definition can be both groups as well as being singular nouns.
Perhaps you can see a link between them that I can't see?
'the one' is the wordplay.
I cannot quite see how this works, but
'the' could be 't' (the is pronounced as a 't' sound in some dialects) and 't' is present in the answer.
'one' could be 'i' (Roman numeral) and 'i' is present in the answer.
This may be the basis of the clue (or it may be nonsense).
'with' acts as a link.
Can you help me to learn more?
(Other definitions for family tree that I've seen before include "Chart of relations" , "Genealogical chart" , "Personal history" .)