One sculpting "Mother and Child" (5)
I believe the answer is:
mason
'one sculpting' is the definition.
'mother and child' is the wordplay.
'mother' becomes 'ma' (Ma is another word for mother or mum).
'and' means one lot of letters go next to another.
'child' becomes 'son' (son is a kind of child).
'ma'+'son'='MASON'
(Other definitions for mason that I've seen before include "Jewish comedian" , "He works with stone - may be free" , "One in lodge" , "Craftsman working in stone" , "one wearing an apron" .)